document_title: All-time Olympic Games medal table

question_text: country with most olympic gold medals all time

text: All-time Olympic Games medal table

text: NOCs with medals[edit]

text: The table is pre-sorted by the name of each Olympic Committee, but can be displayed as sorted by any other column, such as the total number of gold medals or total number of overall medals. To sort by gold, silver, and then bronze, sort first by the bronze column, then the silver, and then the gold. The table does not include revoked medals (e.g. due to doping).

text: Medal totals in this table are current as of the 2018 Winter Olympics in Pyeongchang County, South Korea, and all changes in medal standings due to doping cases up to and including 25 February 2018 are taken into account.

text:
Summer Games
Winter Games
Combined Total

Team (IOC code)

№

01 !

02 !

03 !

Total

№

01 !

02 !

03 !

Total

№

01 !

02 !

03 !

Total

 Afghanistan (AFG)
14
0
0
2
2
0
0
0
0
0
14
0
0
2
2

 Algeria (ALG)
13
5
4
8
17
3
0
0
0
0
16
5
4
8
17

 Argentina (ARG)
24
21
25
28
74
19
0
0
0
0
43
21
25
28
74

 Armenia (ARM)
6
2
6
6
14
7
0
0
0
0
13
2
6
6
14

 Australasia (ANZ) [ANZ]
2
3
4
5
12
0
0
0
0
0
2
3
4
5
12

 Australia (AUS) [AUS] [Z]
26
147
163
187
497
19
5
5
5
15
45
152
168
192
512

 Austria (AUT)
27
18
33
36
87
23
64
81
87
232
50
82
114
123
319

 Azerbaijan (AZE)
6
7
11
25
43
6
0
0
0
0
12
7
11
25
43

 Bahamas (BAH)
16
6
2
6
14
0
0
0
0
0
16
6
2
6
14

 Bahrain (BRN)
9
2
1
0
3
0
0
0
0
0
9
2
1
0
3

 Barbados (BAR) [BAR]
12
0
0
1
1
0
0
0
0
0
12
0
0
1
1

 Belarus (BLR)
6
12
27
39
78
7
8
5
5
18
13
20
32
44
96

 Belgium (BEL)
26
40
53
55
148
21
1
2
3
6
47
41
55
58
154

 Bermuda (BER)
18
0
0
1
1
8
0
0
0
0
26
0
0
1
1

 Bohemia (BOH) [BOH] [Z]
3
0
1
3
4
0
0
0
0
0
3
0
1
3
4

 Botswana (BOT)
10
0
1
0
1
0
0
0
0
0
10
0
1
0
1

 Brazil (BRA)
22
30
36
62
128
8
0
0
0
0
30
30
36
62
128

 British West Indies (BWI) [BWI]
1
0
0
2
2
0
0
0
0
0
1
0
0
2
2

 Bulgaria (BUL) [H]
20
51
87
80
218
20
1
2
3
6
40
52
89
83
224

 Burundi (BDI)
6
1
1
0
2
0
0
0
0
0
6
1
1
0
2

 Cameroon (CMR)
14
3
1
2
6
1
0
0
0
0
15
3
1
2
6

 Canada (CAN)
26
64
102
136
302
23
73
64
62
199
49
137
166
198
501

 Chile (CHI) [I]
23
2
7
4
13
17
0
0
0
0
40
2
7
4
13

 China (CHN) [CHN]
10
224
167
155
546
11
13
28
21
62
21
237
195
176
608

 Colombia (COL)
19
5
9
14
28
2
0
0
0
0
21
5
9
14
28

 Costa Rica (CRC)
15
1
1
2
4
6
0
0
0
0
21
1
1
2
4

 Ivory Coast (CIV) [CIV]
13
1
1
1
3
0
0
0
0
0
13
1
1
1
3

 Croatia (CRO)
7
11
10
12
33
8
4
6
1
11
15
15
16
13
44

 Cuba (CUB) [Z]
20
78
68
79
225
0
0
0
0
0
20
78
68
79
225

 Cyprus (CYP)
10
0
1
0
1
11
0
0
0
0
21
0
1
0
1

 Czech Republic (CZE) [CZE]
6
15
17
24
56
7
9
11
11
31
13
24
28
35
87

 Czechoslovakia (TCH) [TCH]
16
49
49
45
143
16
2
8
15
25
32
51
57
60
168

 Denmark (DEN) [Z]
27
45
74
75
194
14
0
1
0
1
41
45
75
75
195

 Djibouti (DJI) [B]
8
0
0
1
1
0
0
0
0
0
8
0
0
1
1

 Dominican Republic (DOM)
14
3
2
2
7
0
0
0
0
0
14
3
2
2
7

 Ecuador (ECU)
14
1
1
0
2
1
0
0
0
0
15
1
1
0
2

 Egypt (EGY) [EGY] [Z]
22
7
10
15
32
1
0
0
0
0
23
7
10
15
32

 Eritrea (ERI)
5
0
0
1
1
1
0
0
0
0
6
0
0
1
1

 Estonia (EST)
12
9
9
16
34
10
4
2
1
7
22
13
11
17
41

 Ethiopia (ETH)
13
22
11
20
53
2
0
0
0
0
15
22
11
20
53

 Fiji (FIJ)
14
1
0
0
1
3
0
0
0
0
17
1
0
0
1

 Finland (FIN)
25
101
85
117
303
23
43
63
61
167
48
144
148
178
470

 France (FRA) [O] [P] [Z]
28
212
241
263
716
23
36
35
53
124
51
248
276
316
840

 Gabon (GAB)
10
0
1
0
1
0
0
0
0
0
10
0
1
0
1

 Georgia (GEO)
6
8
8
17
33
7
0
0
0
0
13
8
8
17
33

 Germany (GER) [GER] [Z]
16
191
194
230
615
12
92
88
60
240
28
283
282
290
855

 United Team of Germany (EUA) [EUA]
3
28
54
36
118
3
8
6
5
19
6
36
60
41
137

 East Germany (GDR) [GDR]
5
153
129
127
409
6
39
36
35
110
11
192
165
162
519

 West Germany (FRG) [FRG]
5
56
67
81
204
6
11
15
13
39
11
67
82
94
243

 Ghana (GHA) [GHA]
14
0
1
3
4
2
0
0
0
0
16
0
1
3
4

 Great Britain (GBR) [GBR] [Z]
28
263
295
291
849
23
11
4
16
31
51
274
299
307
880

 Greece (GRE) [Z]
28
33
43
40
116
19
0
0
0
0
47
33
43
40
116

 Grenada (GRN)
9
1
1
0
2
0
0
0
0
0
9
1
1
0
2

 Guatemala (GUA)
14
0
1
0
1
1
0
0
0
0
15
0
1
0
1

 Guyana (GUY) [GUY]
17
0
0
1
1
0
0
0
0
0
17
0
0
1
1

 Haiti (HAI) [J]
15
0
1
1
2
0
0
0
0
0
15
0
1
1
2

 Hong Kong (HKG) [HKG]
16
1
1
1
3
5
0
0
0
0
21
1
1
1
3

 Hungary (HUN)
26
175
147
169
491
23
1
2
4
7
49
176
149
173
498

 Iceland (ISL)
20
0
2
2
4
18
0
0
0
0
38
0
2
2
4

 India (IND) [F]
24
9
7
12
28
10
0
0
0
0
34
9
7
12
28

 Indonesia (INA)
15
7
13
12
32
0
0
0
0
0
15
7
13
12
32

 Iran (IRI) [K]
16
19
22
28
69
11
0
0
0
0
27
19
22
28
69

 Iraq (IRQ)
14
0
0
1
1
0
0
0
0
0
14
0
0
1
1

 Ireland (IRL)
21
9
10
12
31
7
0
0
0
0
28
9
10
12
31

 Israel (ISR)
16
1
1
7
9
7
0
0
0
0
23
1
1
7
9

 Italy (ITA) [M] [S]
27
206
178
193
577
23
40
36
48
124
50
246
214
241
701

 Jamaica (JAM) [JAM]
17
22
35
20
77
8
0
0
0
0
25
22
35
20
77

 Japan (JPN)
22
142
135
162
439
21
14
22
22
58
43
156
157
184
497

 Jordan (JOR)
10
1
0
0
1
0
0
0
0
0
10
1
0
0
1

 Kazakhstan (KAZ)
6
15
20
27
62
7
1
3
4
8
13
16
23
31
70

 Kenya (KEN)
14
31
38
33
102
4
0
0
0
0
18
31
38
33
102

 Kosovo (KOS)
1
1
0
0
1
1
0
0
0
0
2
1
0
0
1

 North Korea (PRK)
10
16
16
22
54
9
0
1
1
2
19
16
17
23
56

 South Korea (KOR)
17
90
87
90
267
18
31
25
14
70
35
121
112
104
337

 Kuwait (KUW)
12
0
0
2
2
0
0
0
0
0
12
0
0
2
2

 Kyrgyzstan (KGZ)
6
0
1
3
4
7
0
0
0
0
13
0
1
3
4

 Latvia (LAT)
11
3
11
5
19
11
0
4
4
8
22
3
15
9
27

 Lebanon (LIB)
17
0
2
2
4
17
0
0
0
0
34
0
2
2
4

 Liechtenstein (LIE)
17
0
0
0
0
19
2
2
6
10
36
2
2
6
10

 Lithuania (LTU)
9
6
7
12
25
9
0
0
0
0
18
6
7
12
25

 Luxembourg (LUX) [O]
23
1
1
0
2
9
0
2
0
2
32
1
3
0
4

 Macedonia (MKD)
6
0
0
1
1
6
0
0
0
0
12
0
0
1
1

 Malaysia (MAS) [MAS]
13
0
7
4
11
1
0
0
0
0
14
0
7
4
11

 Mauritius (MRI)
9
0
0
1
1
0
0
0
0
0
9
0
0
1
1

 Mexico (MEX)
23
13
24
32
69
9
0
0
0
0
32
13
24
32
69

 Moldova (MDA)
6
0
2
3
5
7
0
0
0
0
13
0
2
3
5

 Mongolia (MGL)
13
2
10
14
26
14
0
0
0
0
27
2
10
14
26

 Montenegro (MNE)
3
0
1
0
1
3
0
0
0
0
6
0
1
0
1

 Morocco (MAR)
14
6
5
12
23
7
0
0
0
0
21
6
5
12
23

 Mozambique (MOZ)
10
1
0
1
2
0
0
0
0
0
10
1
0
1
2

 Namibia (NAM)
7
0
4
0
4
0
0
0
0
0
7
0
4
0
4

 Netherlands (NED) [Z]
26
85
92
108
285
21
45
44
41
130
47
130
136
149
415

 Netherlands Antilles (AHO) [AHO] [I]
13
0
1
0
1
2
0
0
0
0
15
0
1
0
1

 New Zealand (NZL) [NZL]
23
46
27
44
117
16
0
1
2
3
39
46
28
46
120

 Niger (NIG)
12
0
1
1
2
0
0
0
0
0
12
0
1
1
2

 Nigeria (NGR)
16
3
10
12
25
1
0
0
0
0
17
3
10
12
25

 Norway (NOR) [Q]
25
56
49
47
152
23
132
125
111
368
48
188
174
158
520

 Pakistan (PAK)
17
3
3
4
10
3
0
0
0
0
20
3
3
4
10

 Panama (PAN)
17
1
0
2
3
0
0
0
0
0
17
1
0
2
3

 Paraguay (PAR)
12
0
1
0
1
1
0
0
0
0
13
0
1
0
1

 Peru (PER) [L]
18
1
3
0
4
2
0
0
0
0
20
1
3
0
4

 Philippines (PHI)
21
0
3
7
10
5
0
0
0
0
26
0
3
7
10

 Poland (POL)
21
68
83
133
284
23
7
7
8
22
44
75
90
141
306

 Portugal (POR)
24
4
8
12
24
8
0
0
0
0
32
4
8
12
24

 Puerto Rico (PUR)
18
1
2
6
9
7
0
0
0
0
25
1
2
6
9

 Qatar (QAT)
9
0
1
4
5
0
0
0
0
0
9
0
1
4
5

 Romania (ROU)
21
89
95
122
306
21
0
0
1
1
42
89
95
123
307

 Russia (RUS) [RUS]
6
149
124
153
426
6
47
38
35
120
12
196
162
188
546

 Russian Empire (RU1) [RU1]
3
1
4
3
8
0
0
0
0
0
3
1
4
3
8

 Soviet Union (URS) [URS]
9
395
319
296
1,010
9
78
57
59
194
18
473
376
355
1,204

 Unified Team (EUN) [EUN]
1
45
38
29
112
1
9
6
8
23
2
54
44
37
135

 Saudi Arabia (KSA)
11
0
1
2
3
0
0
0
0
0
11
0
1
2
3

 Samoa (SAM)
9
0
1
0
1
0
0
0
0
0
9
0
1
0
1

 Senegal (SEN)
14
0
1
0
1
5
0
0
0
0
19
0
1
0
1

 Serbia (SRB) [SRB]
4
3
6
6
15
3
0
0
0
0
7
3
6
6
15

 Serbia and Montenegro (SCG) [SCG]
1
0
2
0
2
1
0
0
0
0
2
0
2
0
2

 Singapore (SIN)
16
1
2
2
5
1
0
0
0
0
17
1
2
2
5

 Slovakia (SVK) [SVK]
6
9
12
7
28
7
3
4
1
8
13
12
16
8
36

 Slovenia (SLO)
7
5
8
10
23
8
2
5
10
17
15
7
13
20
40

 South Africa (RSA)
19
26
31
29
86
7
0
0
0
0
26
26
31
29
86

 Spain (ESP) [Z]
23
45
64
41
150
20
1
0
3
4
43
46
64
44
154

 Sri Lanka (SRI) [SRI]
17
0
2
0
2
0
0
0
0
0
17
0
2
0
2

 Sudan (SUD)
12
0
1
0
1
0
0
0
0
0
12
0
1
0
1

 Suriname (SUR) [E]
12
1
0
1
2
0
0
0
0
0
12
1
0
1
2

 Sweden (SWE) [Z]
27
145
170
179
494
23
57
46
55
158
50
202
216
234
652

 Switzerland (SUI)
28
50
75
67
192
23
55
46
52
153
51
105
121
119
345

 Syria (SYR)
13
1
1
1
3
0
0
0
0
0
13
1
1
1
3

 Chinese Taipei (TPE) [TPE] [TPE2]
14
5
7
12
24
12
0
0
0
0
26
5
7
12
24

 Tajikistan (TJK)
6
1
1
2
4
4
0
0
0
0
10
1
1
2
4

 Tanzania (TAN) [TAN]
13
0
2
0
2
0
0
0
0
0
13
0
2
0
2

 Thailand (THA)
16
9
8
16
33
4
0
0
0
0
20
9
8
16
33

 Togo (TOG)
10
0
0
1
1
2
0
0
0
0
12
0
0
1
1

 Tonga (TGA)
9
0
1
0
1
2
0
0
0
0
11
0
1
0
1

 Trinidad and Tobago (TRI) [TRI]
17
2
6
11
19
3
0
0
0
0
20
2
6
11
19

 Tunisia (TUN)
14
4
2
7
13
0
0
0
0
0
14
4
2
7
13

 Turkey (TUR)
22
39
24
28
91
17
0
0
0
0
39
39
24
28
91

 Uganda (UGA)
15
2
3
2
7
0
0
0
0
0
15
2
3
2
7

 Ukraine (UKR)
6
35
30
56
121
7
3
1
4
8
13
38
31
60
129

 United Arab Emirates (UAE)
9
1
0
1
2
0
0
0
0
0
9
1
0
1
2

 United States (USA) [P] [Q] [R] [Z]
27
1,022
795
705
2,522
23
105
110
90
305
50
1,127
905
795
2,827

 Uruguay (URU)
21
2
2
6
10
1
0
0
0
0
22
2
2
6
10

 Uzbekistan (UZB)
6
8
6
17
31
7
1
0
0
1
13
9
6
17
32

 Venezuela (VEN)
18
2
3
10
15
4
0
0
0
0
22
2
3
10
15

 Vietnam (VIE)
15
1
3
0
4
0
0
0
0
0
15
1
3
0
4

 Virgin Islands (ISV)
12
0
1
0
1
7
0
0
0
0
19
0
1
0
1

 Yugoslavia (YUG) [YUG]
18
28
31
31
90
16
0
3
1
4
34
28
34
32
94

 Zambia (ZAM) [ZAM]
13
0
1
1
2
0
0
0
0
0
13
0
1
1
2

 Zimbabwe (ZIM) [ZIM]
13
3
4
1
8
1
0
0
0
0
14
3
4
1
8

 Independent Olympic Athletes (IOA) [IOA]
3
1
0
1
2
0
0
0
0
0
3
1
0
1
2

 Independent Olympic Participants (IOP) [IOP]
1
0
1
2
3
0
0
0
0
0
1
0
1
2
3

 Olympic Athletes from Russia (OAR)
0
0
0
0
0
1
2
6
9
17
1
2
6
9
17

 Mixed team (ZZX) [ZZX]
3
8
5
4
17
0
0
0
0
0
3
8
5
4
17

Totals
28
5,115
5,080
5,482
15,677
23
1,060
1,058
1,050
3,168
51
6,175
6,138
6,532
18,845

text: The sum total of gold, silver and bronze medals are not equal for the following reasons:

text:
Some sports (such as boxing, judo, taekwondo and wrestling) award or have previously awarded two bronze medals per competition.
Some tied performances have resulted in multiple medals of the same colour being awarded for an event. If this tie is for gold or silver, there will be a consequent absence of a silver or bronze medal for that event.
Not all medals which have been revoked have been re-awarded.
Some early events, such as cricket at the 1900 Summer Olympics had only two entrants.
Retroactively awarding gold, silver and bronze medals for the 1896 and 1900 games results in some anomalies, such as the 100 metre freestyle swimming event in 1896 where no surviving records distinguish the places of those who finished between 3rd and 10th position.

text: NOCs without medals[edit]

text: After the 2018 Winter Olympics in Pyeongchang, 71 of the current 206 National Olympic Committees have yet to win an Olympic medal. Seven historic National Olympic Committees and the Refugee Olympic Team are also included in this list.

text:
Team (IOC code)
№ Summer
№ Winter
№ Games

 Albania (ALB)
8
4
12

 American Samoa (ASA)
8
1
9

 Andorra (AND)
11
12
23

 Angola (ANG)
9
0
9

 Antigua and Barbuda (ANT)
10
0
10

 Aruba (ARU)
8
0
8

 Bangladesh (BAN)
9
0
9

 Belize (BIZ) [BIZ]
12
0
12

 Benin (BEN) [BEN]
11
0
11

 Bhutan (BHU)
9
0
9

 Bolivia (BOL)
14
6
20

 Bosnia and Herzegovina (BIH)
7
7
14

 British Virgin Islands (IVB)
9
2
11

 Brunei (BRU) [A]
5
0
5

 Burkina Faso (BUR) [BUR]
9
0
9

 Cambodia (CAM)
9
0
9

 Cape Verde (CPV)
6
0
6

 Cayman Islands (CAY)
10
2
12

 Central African Republic (CAF)
10
0
10

 Chad (CHA)
12
0
12

 Comoros (COM)
6
0
6

 Congo (CGO)
12
0
12

 Democratic Republic of the Congo (COD) [COD]
10
0
10

 Cook Islands (COK)
8
0
8

 Dominica (DMA)
6
1
7

 El Salvador (ESA)
11
0
11

 Equatorial Guinea (GEQ)
9
0
9

 The Gambia (GAM)
9
0
9

 Guam (GUM)
8
1
9

 Guinea (GUI)
11
0
11

 Guinea-Bissau (GBS)
6
0
6

 Honduras (HON)
11
1
12

 Kiribati (KIR)
4
0
4

 Korea (COR)
0
1
1

 Laos (LAO)
9
0
9

 Lesotho (LES)
11
0
11

 Liberia (LBR) [C]
12
0
12

 Libya (LBA) [D]
10
0
10

 Madagascar (MAD)
12
2
14

 Malawi (MAW)
10
0
10

 Maldives (MDV)
8
0
8

 Mali (MLI)
13
0
13

 Malta (MLT)
16
2
18

 Marshall Islands (MHL)
3
0
3

 Mauritania (MTN)
9
0
9

 Federated States of Micronesia (FSM)
5
0
5

 Monaco (MON) [N]
20
10
30

 Myanmar (MYA) [MYA]
17
0
17

 Nauru (NRU)
6
0
6

 Nepal (NEP)
13
4
17

 Nicaragua (NCA)
12
0
12

 Oman (OMA)
9
0
9

 Palau (PLW)
5
0
5

 Palestine (PLE)
6
0
6

 Papua New Guinea (PNG)
10
0
10

 Rwanda (RWA)
9
0
9

 Saint Kitts and Nevis (SKN)
6
0
6

 Saint Lucia (LCA)
6
0
6

 Saint Vincent and the Grenadines (VIN)
8
0
8

 San Marino (SMR)
14
10
24

 São Tomé and Príncipe (STP)
6
0
6

 Seychelles (SEY)
9
0
9

 Sierra Leone (SLE)
11
0
11

 Solomon Islands (SOL)
9
0
9

 Somalia (SOM)
9
0
9

 South Sudan (SSD)
1
0
1

 Swaziland (SWZ)
10
1
11

 East Timor (TLS) [I]
4
2
6

 Turkmenistan (TKM)
6
0
6

 Tuvalu (TUV)
3
0
3

 Vanuatu (VAN)
8
0
8

 Yemen (YEM) [YEM]
7
0
7

 North Borneo (NBO) [NBO]
1
0
1

 Malaya (MAL) [MAL]
2
0
2

 Republic of China (ROC) [ROC]
3
0
3

 Saar (SAA) [SAA]
1
0
1

 North Yemen (YAR) [YAR]
2
0
2

 South Yemen (YMD) [YMD]
1
0
1

 Refugee Olympic Team (ROT) [ROT]
1
0
1

text: Variations[edit]

text: The sections above are based on information published by the International Olympic Committee. Various sources deal with some of the entries in the preceding sections differently.

text: Early Olympics[edit]

text: For the 1900 Summer Olympics several countries are credited with appearances that are not considered official by the IOC. Only one of these cases concerns a medal. A gold medal that is officially added to France's total is given to Luxembourg.[2]

text: Similar cases of disputed nationality affect the 1904 Summer Olympics. France is credited with a silver medal[3] and Norway with two gold medals.[4] In the table above these medals are listed under the United States. Furthermore, Newfoundland is occasionally listed as a separate country at the 1904 Olympics, and would be listed as a historical NOC without medals.[5]

text: Other differences from the official table are based on disagreements about which events were Olympic. This affects several of the events in the 1900 and 1904 Olympics. In addition, some sources include the 1906 Intercalated Games when compiling their medal tables.[6]

text: Germany[edit]

text: Germany has competed under five different designations, including as two separate teams at several Games. Sources vary in how they present the medals won by these teams. The table below shows sourced combinations of these teams, when applied to the updated medal totals from the main table.

text:
Summer Games
Winter Games
Combined Total

Team (IOC code)

№

01 !

02 !

03 !

Total

№

01 !

02 !

03 !

Total

№

01 !

02 !

03 !

Total

 Germany (GER)[7]
16
191
192
232
615
12
92
88
60
240
28
283
280
292
855

 Germany (GER) (EUA)[8]
19
219
246
268
733
15
100
94
65
259
34
319
340
333
992

 Germany (GER) (EUA) (FRG)[9]
24
275
313
349
937
21
111
109
78
298
45
386
422
427
1235

 Germany (GER) (EUA) (FRG) (GDR)[10]
25[11]
428
442
476
1346
21
150
145
113
408
46[11]
578
587
589
1754

text: Russia and the Soviet Union[edit]

text: The Russian Federation and the Russian Empire are often combined outside of IOC sources. The Soviet Union is sometimes combined with the post-union team that competed in 1992. Few sources combine the Soviet Union and Russia as many republics which subsequently gained independence (Armenia, Azerbaijan, Belarus, Estonia, Georgia, Kazakhstan, Kyrgyzstan, Latvia, Lithuania, Moldova, Tadjikistan, Turkmenistan, Ukraine, Uzbekistan) contributed to the medal tally of the USSR.

text:
Summer Games
Winter Games
Combined Total

Team (IOC code)

№

01 !

02 !

03 !

Total

№

01 !

02 !

03 !

Total

№

01 !

02 !

03 !

Total

 Olympic Athletes from Russia (OAR)
0
0
0
0
0
1
2
6
9
17
1
2
6
9
17

 Russia (RUS)[12]
6
149
124
153
426
6
47
38
35
120
12
196
162
188
546

 Russia (RUS) (RU1)[13]
9
150
128
156
434
6
47
38
35
120
15
197
166
191
554

 Soviet Union (URS)[9]
9
395
319
296
1010
9
78
57
59
194
18
473
376
355
1204

 Soviet Union (URS) (EUN)[10]
10
440
357
325
1122
10
87
63
67
217
20
527
420
392
1339

 Russia (RUS) (RU1, OAR)  Soviet Union (URS) (EUN)[14]
19
590
485
481
1556
17
136
107
111
354
36
726
592
592
1910

text: Notes[edit]

text: Obsolete nations notes[edit]

text:
ANZ → AUS , NZL Australasia (ANZ) was a combined team of athletes from Australia (AUS) and New Zealand (NZL). They competed together during the 1908 and 1912 Games.
BOH → TCH → CZE , SVK Prior to the foundation of Czechoslovakia (TCH) after World War I, athletes from Bohemia (BOH) (now part of the present-day Czech Republic) competed in 1900, 1908, and 1912 Games. Czechoslovakia competed in 1920–1992, from 1994 represented by successor NOCs of Czech Republic (CZE) and Slovakia (SVK).
BWI → BAR , JAM , TRI Athletes from Barbados (BAR), Jamaica (JAM), and Trinidad and Tobago (TRI) competed as the British West Indies (BWI) at the 1960 Games. The West Indies Federation only existed as a nation from 1958–1962, so the constituent nations once again competed independently in 1964.
SAA , EUA , GDR , FRG → GER Germany (GER) competed 1896–1952 and from 1992. Due to the partition of Germany after World War II, Germany was represented by two teams at the 1952 Games — Germany (GER) and the Saar (SAA). The Saar was reintegrated back into the Federal Republic of Germany on 1 January 1957, and Saar athletes then competed for Germany. East Germany did not contribute athletes to the 1952 team, as the National Olympic Committee for the German Democratic Republic was only granted "provisional" recognition by the IOC in 1955. For the Games of 1956–1964, Germany participated as a United Team of Germany (EUA), representing the National Olympic Committees of both West Germany and East Germany. Retrospectively, the IOC uses the country code EUA for this team. After the NOC for the German Democratic Republic was granted full recognition by the IOC in 1968, East Germany (GDR) and West Germany (FRG) competed as two independent teams from the 1968 to the 1988 Games.
MAL , NBO → MAS Athletes from Malaya (MAL) and North Borneo (NBO) competed as independent teams at the 1956 Games and Malaya also competed at the 1960 Games, prior to the formation of the Federation of Malaysia (MAS) in 1963.
AHO The Netherlands Antilles (AHO), an autonomous country within the Netherlands (NED), competed 1952–2008. The Netherlands Antilles Olympic Committee's membership in the IOC was withdrawn in 2011 because of the dissolution of the Netherlands Antilles.
RU1 → URS → EUN → RUS Russian Empire (RU1) participated at the 1900, 1908 and 1912 Games prior to the World War I. Soviet Union (URS) competed from 1952 to 1988. Unified Team (EUN) is the generic name used for a combined team of six post-Soviet republics that competed at the 1992 Winter Olympics and a combined team of twelve post-Soviet republics that competed at the 1992 Summer Olympics. Russian Federation (RUS) and the other fourteen post-Soviet republics started competing independently since 1992 (Latvia, Lithuania, Estonia), 1994 or 1996.

SRB , YUG → IOP , SCG Serbia (SRB, 1912, 2006-current) first participated at the Olympic Games in 1912. Yugoslavia (YUG, 1920-1992 Winter) competed as Kingdom of Yugoslavia (officially the Kingdom of Serbs, Croats and Slovenes until 1929) in five Games (1920–1936) before the Second World War. They later competed as Socialist Federal Republic of Yugoslavia for the Games (1948–1992 Winter). This ended with the Breakup of Yugoslavia. Some ex-Yugoslavian nations (Croatia, Slovenia, Bosnia and Herzegovina) have competed as independent teams since 1992. Individual athletes from the Federal Republic of Yugoslavia (Serbia and Montenegro) competed as Independent Olympic Participants (IOP) at the 1992 Summer Games because of sanctions placed by the United Nations. Athletes representing Macedonia likewise competed as independent olympic participants because their NOC had not yet been formed. Since 1996 Macedonia has competed as independent team. The combined team Serbia and Montenegro (SCG, 2004-2006) consisted of the Republic of Serbia and the Republic of Montenegro. They competed as Yugoslavia from (YUG, 1996–2002) and then changed to State Union of Serbia and Montenegro (2004–2006). After 96 years Serbia returned to the Olympics as an independent team at the 2008 Games. Montenegro first participated as an independent team in 2008.
YAR , YMD → YEM Prior to Yemeni unification in 1990, North Yemen participated as the Yemen Arab Republic (YAR) in 1984 and 1988, and South Yemen participated as the Yemen Democratic Republic (YMD) at the 1988 Games. After forming united republic Yemen (YEM) has participated since 1992.
ROC → CHN , TPE The Republic of China was designated as China at the 1932, 1936, and 1948 Games and was representing all of China (including Taiwan). After the Chinese Civil War, the People's Republic of China (CHN) and Chinese Taipei (TPE) have participated as separate teams.
ZZX Special code used by the IOC to refer to medals won by athletes of multiple nations competing together, which was common in early Games (1896–1904). These medals are not included in the respective totals for each nation represented by individual mixed team athletes.
IOA Special code used by the IOC for athletes whose NOC is not recognized by IOC. At the 2000 Summer Olympics four athletes from East Timor competed as Individual Olympic Athletes (IOA). At the 2012 Summer Olympics three athletes from former Netherlands Antilles and one athlete from South Sudan competed as Independent Olympic Athletes (IOA). At the 2016 Summer Olympics nine athletes from Kuwait competed as Independent Olympic Athletes (IOA). Kuwait Olympic Committee had been suspended by the International Olympic Committee (IOC) for the second time in five years due to governmental interference.

text: Name changes notes[edit]

text:
BIZ Belize participated under its former name of British Honduras (HBR) in 1968 and 1972.
BEN Benin was known as Dahomey (DAH) in 1972.
BUR Burkina Faso was known as Upper Volta (VOL) in 1972.
TPE2 After the Chinese Civil War, Chinese Taipei (TPE) participated using the name of the Republic of China at the 1956, 1960, 1972 and 1976 (winter) Games and using Taiwan designation at the 1964 and 1968 Games. In 1979, the IOC started to use Chinese Taipei to refer to the NOC, a compromise that was acceptable for the People's Republic of China (CHN) that led to the start of its participation in the Olympic Games. The name Chinese Taipei was first used in 1984. Participation of the Republic of China, representing all of China (including Taiwan), in 1932, 1936 and 1948 Games are not counted in Taiwan's total participation count.
COD The Democratic Republic of the Congo was known as Zaire (ZAI) between 1984 and 1996.
CIV Côte d'Ivoire was known as Ivory Coast between 1964 and 1988.
EGY Egypt participated as the United Arab Republic (UAR) between 1960 and 1968.
GBR Includes medals won by athletes from the United Kingdom of Great Britain and Ireland (1896–1920) and the United Kingdom of Great Britain and Northern Ireland (1924–present), both of which used the name "Great Britain" and the country code GBR.

GHA Prior to Ghana's independence in 1957, Gold Coast participated in the 1952 Games.
GUY Prior to Guyana's independence in 1966, British Guiana participated from 1948 to 1964.
HKG Totals of Hong Kong (HKG) includes all medals won by athletes representing the Hong Kong National Olympic Committee, designated as "Hong Kong" from 1952–1996 and "Hong Kong, China" since 2000.
MYA Myanmar was known as Burma (BIR) between 1948 and 1988.
SAM Samoa was known as Western Samoa between 1984 and 1996.
SRI Sri Lanka was known as Ceylon (CEY) between 1948 and 1972.
TAN Although Tanganyika and Zanzibar had already merged to form Tanzania in April 1964, the nation was designated Tanganyika in the official report of the 1964 Games.
ZAM Zambia achieved independence on the last day of the 1964 Games, but had participated as Northern Rhodesia (NRH) during those Games.
ZIM Prior to Zimbabwe's independence in 1980, Southern Rhodesia participated as Rhodesia (RHO) in 1928, 1960, and 1964 Games.

text: Participation notes[edit]

text:
A Brunei's participation in the 1988 Games consisted only of a single official, but no competing athletes. This participation is not counted in Brunei's participation total.
B Djibouti at the 2004 Games took part in the Opening Ceremony, but neither athlete competed, so this participation is not counted in Djibouti's participation total.
C Liberia's athletes withdrew from 1980 Games after marching in the Opening Ceremony and took part in the boycott. This participation is not counted in Liberia's participation total.
D Libya marched in the opening ceremony of the 1964 Games, but then withdrew from competition. This participation is not counted in Libya's participation total.
E Suriname at the 1960 Games took part in the Opening Ceremony, but its lone athlete withdrew from Games due to a scheduling error. Participation of Suriname at the 1960 Games not recognized by IOC, so this participation is not counted in Suriname's participation total.

F India's athletes originally competed at the 2014 Games as Independent Olympic Participants and marched under the Olympic Flag during the opening ceremony due to the Indian Olympic Association's suspension. On February 11, 2014, the Indian Olympic Association was reinstated and India's athletes were allowed the option to compete under their own flag from that time onward.
Ia Ib Does not include the participation of Timor-Leste's and Netherlands Antilles's athletes as Individual Olympic Athletes (IOA) at the 2000 Summer Olympics and the 2012 Summer Olympics.
Za Zb Zc Zd Ze Zf Zg Zh Zi Zj Zk Zl Zm Does not include medals won as part of mixed teams with athletes from other nations (1896–1904).

text: Disputed participation notes[edit]

text:
H The Bulgarian Olympic Committee claims that Charles Champaud, a Swiss gymnastics teacher living in Sofia, competed for the nation in 1896. Bulgarian participation at the 1896 Games is recognized by the IOC.
I The Chilean Olympic Committee claims that Luis Subercaseaux Errázuriz, a Chilean diplomat and athlete, competed for the nation in 1896. Chilean participation at the 1896 Games is recognized by the IOC.
J Some sources consider Léon Thiércelin, a fencer who competed at the 1900 Games, of Haitian nationality and therefore the first Olympic appearance by Haiti. Participation of Haiti at the 1900 Games not recognized by the IOC, so this participation is not counted in Haiti's participation total.
K Some sources consider Freydoun Malkom, a fencer who competed at the 1900 Games, of Persian nationality and therefore the first Olympic appearance by Iran. Participation of Iran at the 1900 Games is not recognized by the IOC, so this participation is not counted in Iran's participation total.
L Some sources consider Carlos de Candamo, a fencer who competed at the 1900 Games, of Peruvian nationality and therefore the first Olympic appearance by Peru. Participation of Peru at the 1900 Games is not recognized by the IOC, so this participation is not counted in Peru's participation total.
M Enrico Brusoni's gold medal in the Cycling Men's Points Race at the 1900 Summer Olympics[15] is recognized by the Italian National Olympic Committee, but this race is not recognized by the IOC as a 1900 Summer Olympics event.[16]

N Monaco earned a bronze in the art competitions at the 1924 Summer Olympics.[17] However, medals in art competitions are no longer recognized by the IOC.[18]
Oa Ob Michel Théato, a French athlete who won the gold medal in marathon at the 1900 Games, was born in Luxembourg.[2] The IOC does not recognize Luxembourg participation at the 1900 Games and attributes his medal to France.

The nationalities of many medalists at the 1904 Olympics are disputed as many competitors were recent immigrants to the United States who had not yet been granted US citizenship.

Pa Pb Sources are inconsistent regarding Albert Corey's participation in 1904. Although the Games report refers to Corey as a "Frenchman wearing the colors of the Chicago Athletic Association", the IOC attributes his medal in the marathon to the United States instead of France, and in contradiction, the medal in the four mile team race (that was won by a team of three Americans and Corey) to a mixed team composed of athletes from multiple nations instead of just the United States.
Qa Qb The International Olympic Committee considers Norwegian-American wrestlers Charles Ericksen and Bernhoff Hansen to have competed for the United States; each won a gold medal. In 2012, Norwegian historians however found documentation showing that Ericksen did not receive American citizenship until March 22, 1905, and that Hansen, who was registered as an "alien" as late as 1925, probably never received American citizenship. The historians have therefore petitioned to have the athletes registered as Norwegians.[19][20] In May 2013 it was reported that the Norwegian Olympic Committee had filed a formal application for changing the nationality of the wrestlers in IOC's medal database.[21]
R Bob Fowler, an American marathon runner who competed at the 1904 Games, was a native Newfoundlander, Newfoundland is occasionally listed as a separate country at the 1904 Olympics, and would be listed as an historical NOC without medals.[5] Participation of Newfoundland at the 1904 Games is not recognized by the IOC.
S In 2009, historians from the International Society of Olympic Historians discovered that cyclist Frank Bizzoni formerly thought to be an American athlete was still an Italian citizen when he competed in 1904 being granted US citizenship in 1917.[22][23]


document_title: Chlorofluorocarbon

question_text: when was the problem of cfc's discovered

question_tokens: when was the problem of cfc 's discovered

root

text: Chlorofluorocarbon

text: Structure, properties and production[edit]

text: As in simpler alkanes, carbon in the CFCs bonds with tetrahedral symmetry. Because the fluorine and chlorine atoms differ greatly in size and effective charge from hydrogen and from each other, the methane-derived CFCs deviate from perfect tetrahedral symmetry.[4]

tag: p

text: The physical properties of CFCs and HCFCs are tunable by changes in the number and identity of the halogen atoms. In general, they are volatile but less so than their parent alkanes. The decreased volatility is attributed to the molecular polarity induced by the halides, which induces intermolecular interactions. Thus, methane boils at −161 °C whereas the fluoromethanes boil between −51.7 (CF2H2) and −128 °C (CF4). The CFCs have still higher boiling points because the chloride is even more polarizable than fluoride. Because of their polarity, the CFCs are useful solvents, and their boiling points make them suitable as refrigerants. The CFCs are far less flammable than methane, in part because they contain fewer C-H bonds and in part because, in the case of the chlorides and bromides, the released halides quench the free radicals that sustain flames.

text: The densities of CFCs are higher than their corresponding alkanes. In general, the density of these compounds correlates with the number of chlorides.

text: CFCs and HCFCs are usually produced by halogen exchange starting from chlorinated methanes and ethanes. Illustrative is the synthesis of chlorodifluoromethane from chloroform:

text: The brominated derivatives are generated by free-radical reactions of the chlorofluorocarbons, replacing C-H bonds with C-Br bonds. The production of the anesthetic 2-bromo-2-chloro-1,1,1-trifluoroethane ("halothane") is illustrative:

text: Reactions[edit]

text: The most important reaction[citation needed] of the CFCs is the photo-induced scission of a C-Cl bond:

text: The chlorine atom, written often as Cl., behaves very differently from the chlorine molecule (Cl2). The radical Cl. is long-lived in the upper atmosphere, where it catalyzes the conversion of ozone into O2. Ozone absorbs UV-B radiation, so its depletion allows more of this high energy radiation to reach the Earth's surface. Bromine atoms are even more efficient catalysts; hence brominated CFCs are also regulated.

text: Applications[edit]

text: CFCs and HCFCs are used in a variety of applications because of their low toxicity, reactivity and flammability. Every permutation of fluorine, chlorine and hydrogen based on methane and ethane has been examined and most have been commercialized. Furthermore, many examples are known for higher numbers of carbon as well as related compounds containing bromine. Uses include refrigerants, blowing agents, propellants in medicinal applications and degreasing solvents.

text: Billions of kilograms of chlorodifluoromethane are produced annually as precursor to tetrafluoroethylene, the monomer that is converted into Teflon.[5]

text: Classes of compounds, nomenclature[edit]

text:
Chlorofluorocarbons (CFCs): when derived from methane and ethane these compounds have the formulae CClmF4−m and C2ClmF6−m, where m is nonzero.
Hydro-chlorofluorocarbons (HCFCs): when derived from methane and ethane these compounds have the formula CClmFnH4−m−n and C2ClxFyH6−x−y, where m, n, x, and y are nonzero.
and bromofluorocarbons have formulae similar to the CFCs and HCFCs but also include bromine.
Hydrofluorocarbons (HFCs): when derived from methane, ethane, propane, and butane, these compounds have the respective formulae CFmH4−m, C2FmH6−m, C3FmH8−m, and C4FmH10−m, where m is nonzero.

tag: ul

text: Numbering system[edit]

text: A special numbering system is used for fluorinated alkanes, prefixed with Freon-, R-, CFC- and HCFC-, where the rightmost value indicates the number of fluorine atoms, the next value to the left is the number of hydrogen atoms plus 1, and the next value to the left is the number of carbon atoms less one (zeroes are not stated), and the remaining atoms are chlorine.

text: Freon-12, for example, indicates a methane derivative (only two numbers) containing two fluorine atoms (the second 2) and no hydrogen (1-1=0). It is therefore CCl2F2.

text: Another, easier equation that can be applied to get the correct molecular formula of the CFC/R/Freon class compounds is this to take the numbering and add 90 to it. The resulting value will give the number of carbons as the first numeral, the second numeral gives the number of hydrogen atoms, and the third numeral gives the number of fluorine atoms. The rest of the unaccounted carbon bonds are occupied by chlorine atoms. The value of this equation is always a three figure number. An easy example is that of CFC-12, which gives: 90+12=102 -> 1 carbon, 0 hydrogens, 2 fluorine atoms, and hence 2 chlorine atoms resulting in CCl2F2. The main advantage of this method of deducing the molecular composition in comparison with the method described in the paragraph above is that it gives the number of carbon atoms of the molecule.

text: Freons containing bromine are signified by four numbers. Isomers, which are common for ethane and propane derivatives, are indicated by letters following the numbers :

text:
[hide]Principal CFCs

Systematic name
Common/trivial
name(s), code
Boiling point (°C)
Formula

Trichlorofluoromethane
Freon-11, R-11, CFC-11
23.77
CCl3F

Dichlorodifluoromethane
Freon-12, R-12, CFC-12
−29.8
CCl2F2

Difluoromethane/pentafluoroethane
R-410A, Puron, AZ-20
−48.5
50% CH2F2/50% CHF2CF3

Chlorotrifluoromethane
Freon-13, R-13, CFC-13
−81
CClF3

Chlorodifluoromethane
R-22, HCFC-22
−40.8
CHClF2

Dichlorofluoromethane
R-21, HCFC-21
8.9
CHCl2F

Chlorofluoromethane
Freon 31, R-31, HCFC-31
−9.1
CH2ClF

Bromochlorodifluoromethane
BCF, Halon 1211, H-1211, Freon 12B1
−3.7
CBrClF2

1,1,2-Trichloro-1,2,2-trifluoroethane
Freon 113, R-113, CFC-113, 1,1,2-Trichlorotrifluoroethane
47.7
Cl2FC-CClF2

1,1,1-Trichloro-2,2,2-trifluoroethane
Freon 113a, R-113a, CFC-113a
45.9
Cl3C-CF3

1,2-Dichloro-1,1,2,2-tetrafluoroethane
Freon 114, R-114, CFC-114, Dichlorotetrafluoroethane
3.8
ClF2C-CClF2

1-Chloro-1,1,2,2,2-pentafluoroethane
Freon 115, R-115, CFC-115, Chloropentafluoroethane
−38
ClF2C-CF3

2-Chloro-1,1,1,2-tetrafluoroethane
R-124, HCFC-124
−12
CHFClCF3

1,1-Dichloro-1-fluoroethane
R-141b, HCFC-141b
32
Cl2FC-CH3

1-Chloro-1,1-difluoroethane
R-142b, HCFC-142b
−9.2
ClF2C-CH3

Tetrachloro-1,2-difluoroethane
Freon 112, R-112, CFC-112
91.5
CCl2FCCl2F

Tetrachloro-1,1-difluoroethane
Freon 112a, R-112a, CFC-112a
91.5
CClF2CCl3

1,1,2-Trichlorotrifluoroethane
Freon 113, R-113, CFC-113
48
CCl2FCClF2

1-bromo-2-chloro-1,1,2-trifluoroethane
Halon 2311a
51.7
CHClFCBrF2

2-bromo-2-chloro-1,1,1-trifluoroethane
Halon 2311
50.2
CF3CHBrCl

1,1-Dichloro-2,2,3,3,3-pentafluoropropane
R-225ca, HCFC-225ca
51
CF3CF2CHCl2

1,3-Dichloro-1,2,2,3,3-pentafluoropropane
R-225cb, HCFC-225cb
56
CClF2CF2CHClF

tag: table

text: History[edit]

text: Carbon tetrachloride (CCl4) was used in fire extinguishers and glass "anti-fire grenades" from the late nineteenth century until around the end of World War II. Experimentation with chloroalkanes for fire suppression on military aircraft began at least as early as the 1920s. Freon is a trade name for a group of CFCs which are used primarily as refrigerants, but also have uses in fire-fighting and as propellants in aerosol cans. Bromomethane is widely used as a fumigant. Dichloromethane is a versatile industrial solvent.

text: The Belgian scientist Frédéric Swarts pioneered the synthesis of CFCs in the 1890s. He developed an effective exchange agent to replace chloride in carbon tetrachloride with fluoride to synthesize CFC-11 (CCl3F) and CFC-12 (CCl2F2).

text: In the late 1920s, Thomas Midgley, Jr. improved the process of synthesis and led the effort to use CFC as refrigerant to replace ammonia (NH3), chloromethane (CH3Cl), and sulfur dioxide (SO2), which are toxic but were in common use. In searching for a new refrigerant, requirements for the compound were: low boiling point, low toxicity, and to be generally non-reactive. In a demonstration for the American Chemical Society, Midgley flamboyantly demonstrated all these properties by inhaling a breath of the gas and using it to blow out a candle[6] in 1930.[7][8]

text: Commercial development and use[edit]

text: During World War II, various chloroalkanes were in standard use in military aircraft, although these early halons suffered from excessive toxicity. Nevertheless, after the war they slowly became more common in civil aviation as well. In the 1960s, fluoroalkanes and bromofluoroalkanes became available and were quickly recognized as being highly effective fire-fighting materials. Much early research with Halon 1301 was conducted under the auspices of the US Armed Forces, while Halon 1211 was, initially, mainly developed in the UK. By the late 1960s they were standard in many applications where water and dry-powder extinguishers posed a threat of damage to the protected property, including computer rooms, telecommunications switches, laboratories, museums and art collections. Beginning with warships, in the 1970s, bromofluoroalkanes also progressively came to be associated with rapid knockdown of severe fires in confined spaces with minimal risk to personnel.

text: By the early 1980s, bromofluoroalkanes were in common use on aircraft, ships, and large vehicles as well as in computer facilities and galleries. However, concern was beginning to be expressed about the impact of chloroalkanes and bromoalkanes on the ozone layer. The Vienna Convention for the Protection of the Ozone Layer did not cover bromofluoroalkanes as it was thought, at the time, that emergency discharge of extinguishing systems was too small in volume to produce a significant impact, and too important to human safety for restriction.

text: Regulation[edit]

text: This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (February 2015) (Learn how and when to remove this template message)

text: Since the late 1970s, the use of CFCs has been heavily regulated because of their destructive effects on the ozone layer. After the development of his electron capture detector, James Lovelock was the first to detect the widespread presence of CFCs in the air, finding a mole fraction of 60 ppt of CFC-11 over Ireland. In a self-funded research expedition ending in 1973, Lovelock went on to measure CFC-11 in both the Arctic and Antarctic, finding the presence of the gas in each of 50 air samples collected, and concluding that CFCs are not hazardous to the environment. The experiment did however provide the first useful data on the presence of CFCs in the atmosphere. The damage caused by CFCs was discovered by Sherry Rowland and Mario Molina who, after hearing a lecture on the subject of Lovelock's work, embarked on research resulting in the first publication suggesting the connection in 1974. It turns out that one of CFCs' most attractive features—their low reactivity— is key to their most destructive effects. CFCs' lack of reactivity gives them a lifespan that can exceed 100 years, giving them time to diffuse into the upper stratosphere.[9] Once in the stratosphere, the sun's ultraviolet radiation is strong enough to cause the homolytic cleavage of the C-Cl bond.

text: By 1987, in response to a dramatic seasonal depletion of the ozone layer over Antarctica, diplomats in Montreal forged a treaty, the Montreal Protocol, which called for drastic reductions in the production of CFCs. On 2 March 1989, 12 European Community nations agreed to ban the production of all CFCs by the end of the century. In 1990, diplomats met in London and voted to significantly strengthen the Montreal Protocol by calling for a complete elimination of CFCs by the year 2000. By the year 2010, CFCs should have been completely eliminated from developing countries as well.

text: Because the only CFCs available to countries adhering to the treaty is from recycling, their prices have increased considerably. A worldwide end to production should also terminate the smuggling of this material. However, there are current CFC smuggling issues, as recognized by the United Nations Environmental Programme (UNEP) in a 2006 report titled "Illegal Trade in Ozone Depleting Substances". UNEP estimates that between 16,000–38,000 tonnes of CFCs passed through the black market in the mid-1990s. The report estimated between 7,000 and 14,000 tonnes of CFCs are smuggled annually into developing countries. Asian countries are those with the most smuggling; as of 2007, China, India and South Korea were found to account for around 70% of global CFC production,[10] South Korea later to ban CFC production in 2010.[11] Possible reasons for continued CFC smuggling were also examined: the report noted that many banned CFC producing products have long lifespans and continue to operate. The cost of replacing the equipment of these items is sometimes cheaper than outfitting them with a more ozone-friendly appliance. Additionally, CFC smuggling is not considered a significant issue, so the perceived penalties for smuggling are low. While the eventual phaseout of CFCs is likely, efforts are being taken to stem these current non-compliance problems.

text: By the time of the Montreal Protocol, it was realised that deliberate and accidental discharges during system tests and maintenance accounted for substantially larger volumes than emergency discharges, and consequently halons were brought into the treaty, albeit with many exceptions.

text: Regulatory gap[edit]

text: While the production and consumption of CFCs are regulated under the Montreal Protocol, emissions from existing banks of CFCs are not regulated under the agreement. In 2002, there were an estimated 5,791 kilotons of CFCs in existing products such as refrigerators, air conditioners, aerosol cans and others.[12] Approximately one-third of these CFCs are projected to be emitted over the next decade if action is not taken, posing a threat to both the ozone layer and the climate.[13] A proportion of these CFCs can be safely captured and destroyed.

text: Regulation and DuPont[edit]

text: In 1978 the United States banned the use of CFCs such as Freon in aerosol cans, the beginning of a long series of regulatory actions against their use. The critical DuPont manufacturing patent for Freon ("Process for Fluorinating Halohydrocarbons", U.S. Patent #3258500) was set to expire in 1979. In conjunction with other industrial peers DuPont formed a lobbying group, the "Alliance for Responsible CFC Policy," to combat regulations of ozone-depleting compounds.[14] In 1986 DuPont, with new patents in hand, reversed its previous stance and publicly condemned CFCs.[15] DuPont representatives appeared before the Montreal Protocol urging that CFCs be banned worldwide and stated that their new HCFCs would meet the worldwide demand for refrigerants.[15]

text: Phasing-out of CFCs[edit]

text: Use of certain chloroalkanes as solvents for large scale application, such as dry cleaning, have been phased out, for example, by the IPPC directive on greenhouse gases in 1994 and by the volatile organic compounds (VOC) directive of the EU in 1997. Permitted chlorofluoroalkane uses are medicinal only.

text: Bromofluoroalkanes have been largely phased out and the possession of equipment for their use is prohibited in some countries like the Netherlands and Belgium, from 1 January 2004, based on the Montreal Protocol and guidelines of the European Union.

text: Production of new stocks ceased in most (probably all) countries in 1994.[citation needed] However many countries still require aircraft to be fitted with halon fire suppression systems because no safe and completely satisfactory alternative has been discovered for this application. There are also a few other, highly specialized uses. These programs recycle halon through "halon banks" coordinated by the Halon Recycling Corporation[16] to ensure that discharge to the atmosphere occurs only in a genuine emergency and to conserve remaining stocks.

text: The interim replacements for CFCs are hydrochlorofluorocarbons (HCFCs), which deplete stratospheric ozone, but to a much lesser extent than CFCs.[17] Ultimately, hydrofluorocarbons (HFCs) will replace HCFCs. Unlike CFCs and HCFCs, HFCs have an ozone depletion potential (ODP) of 0.[18] DuPont began producing hydrofluorocarbons as alternatives to Freon in the 1980s. These included Suva refrigerants and Dymel propellants.[19] Natural refrigerants are climate friendly solutions that are enjoying increasing support from large companies and governments interested in reducing global warming emissions from refrigeration and air conditioning. Hydrofluorocarbons are included in the Kyoto Protocol because of their very high Global Warming Potential and are facing calls to be regulated under the Montreal Protocol[dubious – discuss][20] due to the recognition of halocarbon contributions to climate change.[21]

text: On 21 September 2007, approximately 200 countries agreed to accelerate the elimination of hydrochlorofluorocarbons entirely by 2020 in a United Nations-sponsored Montreal summit. Developing nations were given until 2030. Many nations, such as the United States and China, who had previously resisted such efforts, agreed with the accelerated phase out schedule.[22]

text: Development of alternatives for CFCs[edit]

text: Work on alternatives for chlorofluorocarbons in refrigerants began in the late 1970s after the first warnings of damage to stratospheric ozone were published.

text: The hydrochlorofluorocarbons (HCFCs) are less stable in the lower atmosphere, enabling them to break down before reaching the ozone layer. Nevertheless, a significant fraction of the HCFCs do break down in the stratosphere and they have contributed to more chlorine buildup there than originally predicted. Later alternatives lacking the chlorine, the hydrofluorocarbons (HFCs) have an even shorter lifetimes in the lower atmosphere.[17] One of these compounds, HFC-134a, is now used in place of CFC-12 in automobile air conditioners. Hydrocarbon refrigerants (a propane/isobutane blend) are also used extensively in mobile air conditioning systems in Australia, the USA and many other countries, as they have excellent thermodynamic properties and perform particularly well in high ambient temperatures.

text: One of the natural refrigerants (along with ammonia and carbon dioxide), hydrocarbons have negligible environmental impacts and are also used worldwide in domestic and commercial refrigeration applications, and are becoming available in new split system air conditioners.[23] Various other solvents and methods have replaced the use of CFCs in laboratory analytics.[24]

text: In Metered-dose inhalers (MDI), a non-ozone effecting substitute was developed as a propellant, known as "hydrofluoroalkane."[25]

text:
Applications and replacements for CFCs

Application
Previously used CFC
Replacement

Refrigeration & air-conditioning
CFC-12 (CCl2F2); CFC-11(CCl3F); CFC-13(CClF3); HCFC-22 (CHClF2); CFC-113 (Cl2FCCClF2); CFC-114 (CClF2CClF2); CFC-115 (CF3CClF2);
HFC-23 (CHF3); HFC-134a (CF3CFH2); HFC-507 (a 1:1 azeotropic mixture of HFC 125 (CF3 CHF2) and HFC-143a (CF3CH3)); HFC 410 (a 1:1 azeotropic mixture of HFC-32 (CF2H2) and HFC-125 (CF3CF2H))

Propellants in medicinal aerosols
CFC-114 (CClF2CClF2)
HFC-134a (CF3CFH2); HFC-227ea (CF3CHFCF3)

Blowing agents for foams
CFC-11 (CCl3F); CFC 113 (Cl2FCCClF2); HCFC-141b (CCl2FCH3)
HFC-245fa (CF3CH2CHF2); HFC-365 mfc (CF3CH2CF2CH3)

Solvents, degreasing agents, cleaning agents
CFC-11 (CCl3F); CFC-113 (CCl2FCClF2)
None

text: Environmental impacts[edit]

text: As previously discussed, CFCs were phased out via the Montreal Protocol due to their part in ozone depletion. However, the atmospheric impacts of CFCs are not limited to its role as an active ozone reducer. This anthropogenic compound is also a greenhouse gas, with a much higher potential to enhance the greenhouse effect than CO2.

text: Infrared absorption bands trap heat from escaping earth's atmosphere. In the case of CFCs, the strongest of these bands are located in the spectral region 7.8–15.3 µm [26] – referred to as an atmospheric window due to the relative transparency of the atmosphere within this region.[27] The strength of CFC bands and the unique susceptibility of the atmosphere, at which the compound absorbs and emits radiation, are two factors that contribute to CFCs' "super" greenhouse effect.[28] Another such factor is the low concentration of the compound. Because CO2 is close to saturation with high concentrations,[clarification needed] it takes more of the substance to enhance the greenhouse effect. Conversely, the low concentration of CFCs allow their effects to increase linearly with mass.[28]

text: Tracer of ocean circulation[edit]

text: Because the time history of CFC concentrations in the atmosphere is relatively well known, they have provided an important constraint on ocean circulation. CFCs dissolve in seawater at the ocean surface and are subsequently transported into the ocean interior. Because CFCs are inert, their concentration in the ocean interior reflects simply the convolution of their atmospheric time evolution and ocean circulation and mixing.

text: CFC and SF6 tracer-derived age of ocean water[edit]

text: Chlorofluorocarbons (CFCs) are anthropogenic compounds that have been released into the atmosphere since the 1930s in various applications such as in air-conditioning, refrigeration, blowing agents in foams, insulations and packing materials, propellants in aerosol cans, and as solvents.[29] The entry of CFCs into the ocean makes them extremely useful as transient tracers to estimate rates and pathways of ocean circulation and mixing processes.[30] However, due to production restrictions of CFCs in the 1980s, atmospheric concentrations of CFC-11 and CFC-12 has stopped increasing, and the CFC-11 to CFC-12 ratio in the atmosphere have been steadily decreasing, making water dating of water masses more problematic.[30] Incidentally, production and release of sulfur hexafluoride (SF6) have rapidly increased in the atmosphere since the 1970s.[30] Similar to CFCs, SF6 is also an inert gas and is not affected by oceanic chemical or biological activities.[31] Thus, using CFCs in concert with SF6 as a tracer resolves the water dating issues due to decreased CFC concentrations.

text: Using CFCs or SF6 as a tracer of ocean circulation allows for the derivation of rates for ocean processes due to the time-dependent source function. The elapsed time since a subsurface water mass was last in contact with the atmosphere is the tracer-derived age.[32] Estimates of age can be derived based on the partial pressure of an individual compound and the ratio of the partial pressure of CFCs to each other (or SF6).[32]

text: Partial pressure and ratio dating techniques[edit]

text: The age of a water parcel can be estimated by the CFC partial pressure (pCFC) age or SF6 partial pressure (pSF6) age. The pCFC age of a water sample is defined as:

text: where [CFC] is the measured CFC concentration (pmol kg−1) and F is the solubility of CFC gas in seawater as a function of temperature and salinity.[33] The CFC partial pressure is expressed in units of 10–12 atmospheres or parts-per-trillion (ppt).[34] The solubility measurements of CFC-11 and CFC-12 have been previously measured by Warner and Weiss[34] Additionally, the solubility measurement of CFC-113 was measured by Bu and Warner[35] and SF6 by Wanninkhof et al.[36] and Bullister et al.[37] Theses authors mentioned above have expressed the solubility, F, at a total pressure of 1 atm as:

text: where F = solubility expressed in either mol l−1 or mol kg−1 atm−1, T = absolute temperature, S = salinity in parts per thousand (ppt), a1, a2, a3, b1, b2, and b3 are constants to be determined from the least squares fit to the solubility measurements.[35] This equation is derived from the integrated Van 't Hoff equation and the logarithmic Setchenow salinity dependence.[35]

text: It can be noted that the solubility of CFCs increase with decreasing temperature at approximately 1% per degree Celsius.[32]

text: Once the partial pressure of the CFC (or SF6) is derived, it is then compared to the atmospheric time histories for CFC-11, CFC-12, or SF6 in which the pCFC directly corresponds to the year with the same. The difference between the corresponding date and the collection date of the seawater sample is the average age for the water parcel.[32] The age of a parcel of water can also be calculated using the ratio of two CFC partial pressures or the ratio of the SF6 partial pressure to a CFC partial pressure.[32]

text: Safety[edit]

text: According to their material safety data sheets, CFCs and HCFCs are colorless, volatile, toxic liquids and gases with a faintly sweet ethereal odor. Overexposure at concentrations of 11% or more may cause dizziness, loss of concentration, central nervous system depression and/or cardiac arrhythmia. Vapors displace air and can cause asphyxiation in confined spaces. Although non-flammable, their combustion products include hydrofluoric acid, and related species.[38] Normal occupational exposure is rated at 0.07% and does not pose any serious health risks.[39]


document_title: Electromagnetic spectrum

question_text: what is the wavelength of the electromagnetic wave

text: Electromagnetic spectrum

text: History of electromagnetic spectrum discovery

text: For most of history, visible light was the only known part of the electromagnetic spectrum. The ancient Greeks recognized that light traveled in straight lines and studied some of its properties, including reflection and refraction. The study of light continued, and during the 16th and 17th centuries conflicting theories regarded light as either a wave or a particle.[6]

text: The first discovery of electromagnetic radiation other than visible light came in 1800, when William Herschel discovered infrared radiation.[7] He was studying the temperature of different colors by moving a thermometer through light split by a prism. He noticed that the highest temperature was beyond red. He theorized that this temperature change was due to "calorific rays" that were a type of light ray that could not be seen.

text: The next year, Johann Ritter, working at the other end of the spectrum, noticed what he called "chemical rays" (invisible light rays that induced certain chemical reactions). These behaved similarly to visible violet light rays, but were beyond them in the spectrum.[8] They were later renamed ultraviolet radiation.

text: Electromagnetic radiation was first linked to electromagnetism in 1845, when Michael Faraday noticed that the polarization of light traveling through a transparent material responded to a magnetic field (see Faraday effect). During the 1860s James Maxwell developed four partial differential equations for the electromagnetic field. Two of these equations predicted the possibility and behavior of waves in the field. Analyzing the speed of these theoretical waves, Maxwell realized that they must travel at a speed that was about the known speed of light. This startling coincidence in value led Maxwell to make the inference that light itself is a type of electromagnetic wave.

text: Maxwell's equations predicted an infinite number of frequencies of electromagnetic waves, all traveling at the speed of light. This was the first indication of the existence of the entire electromagnetic spectrum.

text: Maxwell's predicted waves included waves at very low frequencies compared to infrared, which in theory might be created by oscillating charges in an ordinary electrical circuit of a certain type. Attempting to prove Maxwell's equations and detect such low frequency electromagnetic radiation, in 1886 the physicist Heinrich Hertz built an apparatus to generate and detect what are now called radio waves. Hertz found the waves and was able to infer (by measuring their wavelength and multiplying it by their frequency) that they traveled at the speed of light. Hertz also demonstrated that the new radiation could be both reflected and refracted by various dielectric media, in the same manner as light. For example, Hertz was able to focus the waves using a lens made of tree resin. In a later experiment, Hertz similarly produced and measured the properties of microwaves. These new types of waves paved the way for inventions such as the wireless telegraph and the radio.

text: In 1895 Wilhelm Röntgen noticed a new type of radiation emitted during an experiment with an evacuated tube subjected to a high voltage. He called these radiations x-rays and found that they were able to travel through parts of the human body but were reflected or stopped by denser matter such as bones. Before long, many uses were found for them in the field of medicine.

text: The last portion of the electromagnetic spectrum was filled in with the discovery of gamma rays. In 1900 Paul Villard was studying the radioactive emissions of radium when he identified a new type of radiation that he first thought consisted of particles similar to known alpha and beta particles, but with the power of being far more penetrating than either. However, in 1910, British physicist William Henry Bragg demonstrated that gamma rays are electromagnetic radiation, not particles, and in 1914, Ernest Rutherford (who had named them gamma rays in 1903 when he realized that they were fundamentally different from charged alpha and beta particles) and Edward Andrade measured their wavelengths, and found that gamma rays were similar to X-rays, but with shorter wavelengths and higher frequencies.

text: Range of the spectrum

text: Electromagnetic waves are typically described by any of the following three physical properties: the frequency f, wavelength λ, or photon energy E. Frequencies observed in astronomy range from 7023239999999999999♠2.4×1023 Hz (1 GeV gamma rays) down to the local plasma frequency of the ionized interstellar medium (~1 kHz). Wavelength is inversely proportional to the wave frequency,[5] so gamma rays have very short wavelengths that are fractions of the size of atoms, whereas wavelengths on the opposite end of the spectrum can be as long as the universe. Photon energy is directly proportional to the wave frequency, so gamma ray photons have the highest energy (around a billion electron volts), while radio wave photons have very low energy (around a femtoelectronvolt). These relations are illustrated by the following equations:

text: where:

text:
c = 7008299792458000000♠299792458 m/s is the speed of light in a vacuum
h = 6966662606895999999♠6.62606896(33)×10−34 J·s = 6985413566733000000♠4.13566733(10)×10−15 eV·s is Planck's constant.[9]

text: Whenever electromagnetic waves exist in a medium with matter, their wavelength is decreased. Wavelengths of electromagnetic radiation, no matter what medium they are traveling through, are usually quoted in terms of the vacuum wavelength, although this is not always explicitly stated.

text: Generally, electromagnetic radiation is classified by wavelength into radio wave, microwave, terahertz (or sub-millimeter) radiation, infrared, the visible region that is perceived as light, ultraviolet, X-rays and gamma rays. The behavior of EM radiation depends on its wavelength. When EM radiation interacts with single atoms and molecules, its behavior also depends on the amount of energy per quantum (photon) it carries.

text: Spectroscopy can detect a much wider region of the EM spectrum than the visible range of 400 nm to 700 nm. A common laboratory spectroscope can detect wavelengths from 2 nm to 2500 nm.[citation needed] Detailed information about the physical properties of objects, gases, or even stars can be obtained from this type of device. Spectroscopes are widely used in astrophysics. For example, many hydrogen atoms emit a radio wave photon that has a wavelength of 21.12 cm. Also, frequencies of 30 Hz and below can be produced by and are important in the study of certain stellar nebulae[10] and frequencies as high as 7027290000000000000♠2.9×1027 Hz have been detected from astrophysical sources.[11]

text: Rationale for spectrum regional names

text: Electromagnetic radiation interacts with matter in different ways across the spectrum. These types of interaction are so different that historically different names have been applied to different parts of the spectrum, as though these were different types of radiation. Thus, although these "different kinds" of electromagnetic radiation form a quantitatively continuous spectrum of frequencies and wavelengths, the spectrum remains divided for practical reasons related to these qualitative interaction differences.

text:
Electromagnetic radiation interaction with matter

Region of the spectrum
Main interactions with matter

Radio
Collective oscillation of charge carriers in bulk material (plasma oscillation). An example would be the oscillatory travels of the electrons in an antenna.

Microwave through far infrared
Plasma oscillation, molecular rotation

Near infrared
Molecular vibration, plasma oscillation (in metals only)

Visible
Molecular electron excitation (including pigment molecules found in the human retina), plasma oscillations (in metals only)

Ultraviolet
Excitation of molecular and atomic valence electrons, including ejection of the electrons (photoelectric effect)

X-rays
Excitation and ejection of core atomic electrons, Compton scattering (for low atomic numbers)

Gamma rays
Energetic ejection of core electrons in heavy elements, Compton scattering (for all atomic numbers), excitation of atomic nuclei, including dissociation of nuclei

High-energy gamma rays
Creation of particle-antiparticle pairs. At very high energies a single photon can create a shower of high-energy particles and antiparticles upon interaction with matter.

text: Types of radiation

text: Boundaries

text: A discussion of the regions (or bands or types) of the electromagnetic spectrum is given below. Note that there are no precisely defined boundaries between the bands of the electromagnetic spectrum; rather they fade into each other like the bands in a rainbow (which is the sub-spectrum of visible light). Radiation of each frequency and wavelength (or in each band) has a mix of properties of the two regions of the spectrum that bound it. For example, red light resembles infrared radiation in that it can excite and add energy to some chemical bonds and indeed must do so to power the chemical mechanisms responsible for photosynthesis and the working of the visual system.

text: Regions of the spectrum

text: The types of electromagnetic radiation are broadly classified into the following classes:[5]

text:
Gamma radiation
X-ray radiation
Ultraviolet radiation
Visible radiation
Infrared radiation
Terahertz radiation
Microwave radiation
Radio waves

tag: ol

text: This classification goes in the increasing order of wavelength, which is characteristic of the type of radiation.[5] While, in general, the classification scheme is accurate, in reality there is often some overlap between neighboring types of electromagnetic energy. For example, SLF radio waves at 60 Hz may be received and studied by astronomers, or may be ducted along wires as electric power, although the latter is, in the strict sense, not electromagnetic radiation at all (see near and far field).

text: The distinction between X-rays and gamma rays is partly based on sources: the photons generated from nuclear decay or other nuclear and subnuclear/particle process, are always termed gamma rays, whereas X-rays are generated by electronic transitions involving highly energetic inner atomic electrons.[12][13][14] In general, nuclear transitions are much more energetic than electronic transitions, so gamma-rays are more energetic than X-rays, but exceptions exist. By analogy to electronic transitions, muonic atom transitions are also said to produce X-rays, even though their energy may exceed 6 megaelectronvolts (0.96 pJ),[15] whereas there are many (77 known to be less than 10 keV (1.6 fJ)) low-energy nuclear transitions (e.g., the 7.6 eV (1.22 aJ) nuclear transition of thorium-229), and, despite being one million-fold less energetic than some muonic X-rays, the emitted photons are still called gamma rays due to their nuclear origin.[16]

text: The convention that EM radiation that is known to come from the nucleus, is always called "gamma ray" radiation is the only convention that is universally respected, however. Many astronomical gamma ray sources (such as gamma ray bursts) are known to be too energetic (in both intensity and wavelength) to be of nuclear origin. Quite often, in high energy physics and in medical radiotherapy, very high energy EMR (in the >10 MeV region)—which is of higher energy than any nuclear gamma ray—is not called X-ray or gamma-ray, but instead by the generic term of "high energy photons."

text: The region of the spectrum where a particular observed electromagnetic radiation falls, is reference frame-dependent (due to the Doppler shift for light), so EM radiation that one observer would say is in one region of the spectrum could appear to an observer moving at a substantial fraction of the speed of light with respect to the first to be in another part of the spectrum. For example, consider the cosmic microwave background. It was produced, when matter and radiation decoupled, by the de-excitation of hydrogen atoms to the ground state. These photons were from Lyman series transitions, putting them in the ultraviolet (UV) part of the electromagnetic spectrum. Now this radiation has undergone enough cosmological red shift to put it into the microwave region of the spectrum for observers moving slowly (compared to the speed of light) with respect to the cosmos.

text: Radio frequency

text: Radio waves are emitted and received by antennas, which consist of conductors such as metal rod resonators. In artificial generation of radio waves, an electronic device called a transmitter generates an AC electric current which is applied to an antenna. The oscillating electrons in the antenna generate oscillating electric and magnetic fields that radiate away from the antenna as radio waves. In reception of radio waves, the oscillating electric and magnetic fields of a radio wave couple to the electrons in an antenna, pushing them back and forth, creating oscillating currents which are applied to a radio receiver. Earth's atmosphere is mainly transparent to radio waves, except for layers of charged particles in the ionosphere which can reflect certain frequencies.

text: Radio waves are extremely widely used to transmit information across distances in radio communication systems such as radio broadcasting, television, two way radios, mobile phones, communication satellites, and wireless networking. In a radio communication system, a radio frequency current is modulated with an information-bearing signal in a transmitter by varying either the amplitude, frequency or phase, and applied to an antenna. The radio waves carry the information across space to a receiver, where they are received by an antenna and the information extracted by demodulation in the receiver. Radio waves are also used for navigation in systems like Global Positioning System (GPS) and navigational beacons, and locating distant objects in radiolocation and radar. They are also used for remote control, and for industrial heating.

text: The use of the radio spectrum is strictly regulated by governments, coordinated by a body called the International Telecommunications Union (ITU) which allocates frequencies to different users for different uses.

text: Microwaves

text: Microwaves are radio waves of short wavelength, from about 10 centimeters to one millimeter, in the SHF and EHF frequency bands. Microwave energy is produced with klystron and magnetron tubes, and with solid state devices such as Gunn and IMPATT diodes. Although they are emitted and absorbed by short antennas, they are also absorbed by polar molecules, coupling to vibrational and rotational modes, resulting in bulk heating. Unlike higher frequency waves such as infrared and light which are absorbed mainly at surfaces, microwaves can penetrate into materials and deposit their energy below the surface. This effect is used to heat food in microwave ovens, and for industrial heating and medical diathermy. Microwaves are the main wavelengths used in radar, and are used for satellite communication, and wireless networking technologies such as Wifi, although this is at intensity levels unable to cause thermal heating. The copper cables (transmission lines) which are used to carry lower frequency radio waves to antennas have excessive power losses at microwave frequencies, and metal pipes called waveguides are used to carry them. Although at the low end of the band the atmosphere is mainly transparent, at the upper end of the band absorption of microwaves by atmospheric gasses limits practical propagation distances to a few kilometers.

text: Terahertz radiation

text: Terahertz radiation is a region of the spectrum between far infrared and microwaves. Until recently, the range was rarely studied and few sources existed for microwave energy at the high end of the band (sub-millimeter waves or so-called terahertz waves), but applications such as imaging and communications are now appearing. Scientists are also looking to apply terahertz technology in the armed forces, where high-frequency waves might be directed at enemy troops to incapacitate their electronic equipment.[17] Terahertz radiation is strongly absorbed by atmospheric gases, making this frequency range useless for long distance communication.

text: Infrared radiation

text: The infrared part of the electromagnetic spectrum covers the range from roughly 300 GHz to 400 THz (1 mm - 750 nm). It can be divided into three parts:[5]

text:
Far-infrared, from 300 GHz to 30 THz (1 mm – 10 μm). The lower part of this range may also be called microwaves or terahertz waves. This radiation is typically absorbed by so-called rotational modes in gas-phase molecules, by molecular motions in liquids, and by phonons in solids. The water in Earth's atmosphere absorbs so strongly in this range that it renders the atmosphere in effect opaque. However, there are certain wavelength ranges ("windows") within the opaque range that allow partial transmission, and can be used for astronomy. The wavelength range from approximately 200 μm up to a few mm is often referred to as "sub-millimeter" in astronomy, reserving far infrared for wavelengths below 200 μm.
Mid-infrared, from 30 to 120 THz (10–2.5 μm). Hot objects (black-body radiators) can radiate strongly in this range, and human skin at normal body temperature radiates strongly at the lower end of this region. This radiation is absorbed by molecular vibrations, where the different atoms in a molecule vibrate around their equilibrium positions. This range is sometimes called the fingerprint region, since the mid-infrared absorption spectrum of a compound is very specific for that compound.
Near-infrared, from 120 to 400 THz (2,500–750 nm). Physical processes that are relevant for this range are similar to those for visible light. The highest frequences in this region can be detected directly by some types of photographic film, and by many types of solid state image sensors for infrared photography and videography.

text: Visible radiation (light)

text: Above infrared in frequency comes visible light. The Sun emits its peak power in the visible region, although integrating the entire emission power spectrum through all wavelengths shows that the Sun emits slightly more infrared than visible light.[18] By definition, visible light is the part of the EM spectrum the human eye is the most sensitive to. Visible light (and near-infrared light) is typically absorbed and emitted by electrons in molecules and atoms that move from one energy level to another. This action allows the chemical mechanisms that underlie human vision and plant photosynthesis. The light that excites the human visual system is a very small portion of the electromagnetic spectrum. A rainbow shows the optical (visible) part of the electromagnetic spectrum; infrared (if it could be seen) would be located just beyond the red side of the rainbow with ultraviolet appearing just beyond the violet end.

text: Electromagnetic radiation with a wavelength between 380 nm and 760 nm (400–790 terahertz) is detected by the human eye and perceived as visible light. Other wavelengths, especially near infrared (longer than 760 nm) and ultraviolet (shorter than 380 nm) are also sometimes referred to as light, especially when the visibility to humans is not relevant. White light is a combination of lights of different wavelengths in the visible spectrum. Passing white light through a prism splits it up into the several colors of light observed in the visible spectrum between 400 nm and 780 nm.

text: If radiation having a frequency in the visible region of the EM spectrum reflects off an object, say, a bowl of fruit, and then strikes the eyes, this results in visual perception of the scene. The brain's visual system processes the multitude of reflected frequencies into different shades and hues, and through this insufficiently-understood psychophysical phenomenon, most people perceive a bowl of fruit.

text: At most wavelengths, however, the information carried by electromagnetic radiation is not directly detected by human senses. Natural sources produce EM radiation across the spectrum, and technology can also manipulate a broad range of wavelengths. Optical fiber transmits light that, although not necessarily in the visible part of the spectrum (it is usually infrared), can carry information. The modulation is similar to that used with radio waves.

text: Ultraviolet radiation

text: Next in frequency comes ultraviolet (UV). The wavelength of UV rays is shorter than the violet end of the visible spectrum but longer than the X-ray.

text: UV is the longest wavelength radiation whose photons are energetic enough to ionize atoms, separating electrons from them, and thus causing chemical reactions. Short wavelength UV and the shorter wavelength radiation above it (X-rays and gamma rays) are called ionizing radiation, and exposure to them can damage living tissue, making them a health hazard. UV can also cause many substances to glow with visible light; this is called fluorescence.

text: At the middle range of UV, UV rays cannot ionize but can break chemical bonds, making molecules unusually reactive. Sunburn, for example, is caused by the disruptive effects of middle range UV radiation on skin cells, which is the main cause of skin cancer. UV rays in the middle range can irreparably damage the complex DNA molecules in the cells producing thymine dimers making it a very potent mutagen.

text: The Sun emits significant UV radiation (about 10% of its total power), including extremely short wavelength UV that could potentially destroy most life on land (ocean water would provide some protection for life there). However, most of the Sun's damaging UV wavelengths are absorbed by the atmosphere before they reach the surface. The higher energy (shortest wavelength) ranges of UV (called "vacuum UV") are absorbed by nitrogen and, at longer wavelengths, by simple diatomic oxygen in the air. Most of the UV in the mid-range of energy is blocked by the ozone layer, which absorbs strongly in the important 200–315 nm range, the lower energy part of which is too long for ordinary dioxygen in air to absorb. This leaves less than 3% of sunlight at sea level in UV, with all of this remainder at the lower energies. The remainder is UV-A, along with some UV-B. The very lowest energy range of UV between 315 nm and visible light (called UV-A) is not blocked well by the atmosphere, but does not cause sunburn and does less biological damage. However, it is not harmless and does create oxygen radicals, mutations and skin damage. See ultraviolet for more information.

text: X-rays

text: After UV come X-rays, which, like the upper ranges of UV are also ionizing. However, due to their higher energies, X-rays can also interact with matter by means of the Compton effect. Hard X-rays have shorter wavelengths than soft X-rays and as they can pass through many substances with little absorption, they can be used to 'see through' objects with 'thicknesses' less than that equivalent to a few meters of water. One notable use is diagnostic X-ray imaging in medicine (a process known as radiography). X-rays are useful as probes in high-energy physics. In astronomy, the accretion disks around neutron stars and black holes emit X-rays, enabling studies of these phenomena. X-rays are also emitted by the coronas of stars and are strongly emitted by some types of nebulae. However, X-ray telescopes must be placed outside the Earth's atmosphere to see astronomical X-rays, since the great depth of the atmosphere of Earth is opaque to X-rays (with areal density of 1000 grams per cm2), equivalent to 10 meters thickness of water.[19] This is an amount sufficient to block almost all astronomical X-rays (and also astronomical gamma rays—see below).

text: Gamma rays

text: After hard X-rays come gamma rays, which were discovered by Paul Ulrich Villard in 1900. These are the most energetic photons, having no defined lower limit to their wavelength. In astronomy they are valuable for studying high-energy objects or regions, however as with X-rays this can only be done with telescopes outside the Earth's atmosphere. Gamma rays are used experimentally by physicists for their penetrating ability and are produced by a number of radioisotopes. They are used for irradiation of foods and seeds for sterilization, and in medicine they are occasionally used in radiation cancer therapy.[20] More commonly, gamma rays are used for diagnostic imaging in nuclear medicine, an example being PET scans. The wavelength of gamma rays can be measured with high accuracy through the effects of Compton scattering.


document_title: List of American Idol alumni album sales in the United States

question_text: who has sold more albums kelly or carrie

text: Artists with RIAA certified albums[edit]

text: This first list only includes contestants with at least one certified album for units shipped in U.S. (Gold, Platinum, and/or Multi-platinum). Total albums sold listed in this pages for each artist is shown first. The numbers in parentheses are for sales for all albums including EPs and compilations which may not be listed here.

text:
Contestant
Total sales
First album
Second album
Third album
Fourth album
Fifth album
Sixth album
Seventh album
Eighth album

1.
Carrie Underwood
(season 4, winner)
16,389,000[1]
Some Hearts
(November 15, 2005)
Arista Nashville
7,450,000[2]
8x Platinum[3]
Peak: #2
Carnival Ride
(October 23, 2007)
Arista Nashville
3,400,000[4]
4x Platinum[5]
Peak: #1
Play On
(November 3, 2009)
Arista Nashville
2,300,000[4]
3x Platinum[6]
Peak: #1
Blown Away
(May 1, 2012)
Arista Nashville
1,794,800[7]
2x Platinum[8]
Peak: #1
Storyteller
(October 23, 2015)
Arista Nashville
752,100[9]
Platinum[10]
Peak: #2

2.
Kelly Clarkson
(season 1, winner)
14,150,000
Thankful
(April 15, 2003)
RCA
2,800,000[1]
2x Platinum[11]
Peak: #1
Breakaway
(November 30, 2004)
RCA
6,355,000[1]
6x Platinum[12]
Peak: #3
My December
(June 26, 2007)
RCA
858,000[1]
Platinum[13]
Peak: #2
All I Ever Wanted
(March 10, 2009)
RCA
1,004,000[1]
N/A
Peak: #1
Stronger
(October 24, 2011)
RCA
1,129,000[1]
Platinum[14]
Peak: #2
Wrapped in Red
(October 29, 2013)
RCA
942,000[1]
Platinum[15]
Peak: #3
Piece by Piece
(March 3, 2015)
RCA
284,000[1]
Gold
Peak: #1
Meaning of Life
(October 27, 2017)
Atlantic[16]

3.
Chris Daughtry
(as Daughtry)
(season 5, 4th place)
7,352,000[17]
Daughtry
(November 21, 2006)
RCA
5,040,000[2]
4x Platinum[18]
Peak: #1
Leave This Town
(July 14, 2009)
RCA
1,357,000[19]
Platinum[18]
Peak: #1
Break the Spell
(November 21, 2011)
RCA
513,000[20]
Gold[21]
Peak: #8
Baptized
(November 19, 2013)
RCA
270,000[22]
N/A
Peak: #6
TBD
(2017)
RCA

4.
Clay Aiken
(season 2, runner-up)
5,069,000[17]
Measure of a Man
(October 14, 2003)
RCA
2,786,000[23]
2x Platinum[24]
Peak: #1
Merry Christmas with Love
(November 16, 2004)
RCA
1,416,000[25]
Platinum[24]
Peak: #4
A Thousand Different Ways
(September 19, 2006)
RCA
531,000[26]
Gold[24]
Peak: #2
On My Way Here
(May 6, 2008)
RCA
165,000[26]
N/A
Peak: #4
Tried and True / Steadfast
(June 1, 2010) / (March 26, 2012)
Decca / Universal
80,000 note 1[27]
N/A
Peak: #9 / #120

5.
Fantasia Barrino
(season 3, winner)
3,332,000[17]
Free Yourself
(November 23, 2004)
J Records
1,839,000[23]
Platinum[28]
Peak: #8
Fantasia
(December 12, 2006)
J Records
530,000[29]
Gold[28]
Peak: #19
Back to Me
(August 24, 2010)
J Records
490,000[30]
N/A
Peak: #2
Side Effects of You
(April 23, 2013)
RCA
300,000[31]
Peak: #2
The Definition Of...
(July 28, 2016)
RCA
32,000[32]
Peak: #6

6.
Ruben Studdard
(season 2, winner)
2,644,000[17]
Soulful
(December 9, 2003)
J Records
1,792,000[23]
Platinum[33]
Peak: #1
I Need an Angel
(November 23, 2004)
J Records
483,000[34]
Gold[33]
Peak: #20
The Return
(October 17, 2006)
J Records
238,000[34]
N/A
Peak: #8
Love Is
(May 19, 2009)
Hickory Records
50,000[35]
N/A
Peak: #36
Letters from Birmingham
(March 13, 2012)
Shanachie
17,000[36]
N/A
Peak: #150
Unconditional Love
(February 4, 2014)
The Verve Music Group
6,000[37]
N/A
Peak: #46

7.
Scotty McCreery
(season 10, winner)
2,165,000[17]
Clear as Day
(October 4, 2011)
Mercury Nashville
1,166,000[38]
Platinum[39]
Peak: #1
Christmas With Scotty McCreery
(October 16, 2012)
Mercury Nashville
382,000[40]
Gold[41]
Peak: #4
See You Tonight
(October 15, 2013)
Mercury Nashville
269,900[42]
N/A
Peak: #6

8.
Kellie Pickler
(season 5, 6th place)
1,557,000[17]
Small Town Girl
(October 31, 2006)
BNA
900,000[43]
Gold[44]
Peak: #9
Kellie Pickler
(September 30, 2008)
BNA
470,000[43]
N/A
Peak: #9
100 Proof
(January 24, 2012)
BNA
90,000[43]
N/A
Peak: #7
The Woman I Am
November 11, 2013
Black River Entertainment
47,000[45]
N/A
Peak: #19

9.
David Cook
(season 7, winner)
1,510,000[4]
David Cook
(November 18, 2008)
RCA
1,380,000[19]
Platinum[46]
Peak: #3
This Loud Morning
(June 28, 2011)
RCA
133,000[47]
N/A
Peak: #7
Digital Vein
(September 18, 2015)
InGrooves Music
11,000[48]
N/A
Peak: #35

10.
Phillip Phillips
(season 11, winner)
1,490,000[17]
The World from the Side of the Moon
(November 19, 2012)
Interscope
1,033,000[49]
Platinum[50]
Peak: #4
Behind the Light
(May 19, 2014)
Interscope
123,000[51]
N/A
Peak: #7

11.
Jennifer Hudson
(season 3, 7th place)
1,446,000[52]
Jennifer Hudson
(September 30, 2008)
Arista
839,000[53]
Gold[54]
Peak: #2
I Remember Me
(March 22, 2011)
Arista
459,000[55]
Gold[54]
Peak: #2
JHUD
(September 23, 2014)
RCA
61,000[51]
N/A
Peak: #10

12.
Jordin Sparks
(season 6, winner)
1,313,000[56]
Jordin Sparks
(November 20, 2007)
Jive
1,056,000[19]
Platinum[57]
Peak: #10
Battlefield
(July 21, 2009)
Jive
190,000[58]
N/A
Peak: #7
Right Here, Right Now
(August 21, 2015)
Louder Than Life
N/A
Peak: #161

13.
Adam Lambert
(season 8, runner-up)
1,291,000[59]
For Your Entertainment
(November 23, 2009)
RCA
863,000[60]
Gold[61]
Peak: #3
Trespassing
(May 15, 2012)
RCA
197,000[62]
N/A
Peak: #1
The Original High
(June 16, 2015)
Warner Bros Records
52,000[63]
N/A
Peak: #3

14.
David Archuleta
(season 7, runner-up)
1,156,000[52]
David Archuleta
(November 11, 2008)
Jive
765,000[64]
Gold[65]
Peak: #2
Christmas from the Heart
(October 13, 2009)
Jive
246,000[66]
N/A
Peak: #30
The Other Side of Down
(October 5, 2010)
Jive
67,000[64]
N/A
Peak: #13
Begin.
(August 7, 2012)
Highway Records
14,000[67]
N/A
Peak: #28
No Matter How Far
(2013)
E1 Music
5,000[68]
N/A
Peak: #110

15.
Josh Gracin
(season 2, 4th place)
804,000[56]
Josh Gracin
(June 15, 2004)
Lyric Street
703,000[69]
Gold[70]
Peak: #11
We Weren't Crazy
(April 1, 2008)
Lyric Street
86,000[71]
N/A
Peak: #33
Redemption
(November 8, 2011)
Average Joe's
4,000[72]
N/A
Peak: N/A

16.
Taylor Hicks
(season 5, winner)
768,000[52]
Taylor Hicks
(December 12, 2006)
Arista
705,000[53]
Platinum[73]
Peak: #2
The Distance
(March 10, 2009)
Modern Whomp
52,000[69]
N/A
Peak: #58

17.
Bo Bice
(season 4, runner-up)
757,000[52]
The Real Thing
(December 13, 2005)
RCA
673,000[53]
Gold[74]
Peak: #4
See the Light
(October 23, 2007)
StratArt
62,000[75]
N/A
Peak: #150
3
(May 18, 2010)
Saguaro Road
11,000[76]
N/A
Peak: #154

18.
Elliott Yamin
(season 5, 3rd place)
696,000[56]
Elliott Yamin
(March 20, 2007)
Hickory Records
RED Distribution
527,000[77]
Gold[78]
Peak: #3
Sounds of the Season
(October 14, 2007)
Hickory Records
81,000[79]
N/A
Peak: #32
My Kind of Holiday
(October 7, 2008)
TRP Records,
Fontana Distribution
27,000[80]
N/A
Peak: #162
Fight For Love
(May 5, 2009)
Hickory Records
49,000[77]
N/A
Peak: #26
Let's Get to What's Real
(March 27, 2012)
E1/Purpose Music Group
2,000[81]
N/A
Peak: N/A

text: ^Note 1 Aiken's album, Tried & True was re-packaged and re-released by Decca under the new name, Steadfast, concurrent with his appearance on The Celebrity Apprentice in 2012

text: Artists without RIAA certified albums[edit]

text: The following is a list of other American Idol alumni album sales and reflects that commercial success can be achieved through association with American Idol and with post-Idol promotion, although the degree of success varies considerably. This list only includes contestants who have numbers available, and again does not include EPs, American Idol compilations, or pre-Idol recordings, numbers in parentheses however may include sales from these releases:

text:
Rank
Former Contestant
Total Sales
Albums

19.
Mandisa
(season 5, 9th place)
928,000[82]

True Beauty (2007) #43 — 226,000[83]
It's Christmas (2008) #85 — 64,000[84]
Freedom (2009) #83 — 152,000[85]
What If We Were Real (2011) #66 — 270,000[86]
Overcomer (2013) #29 - 140,000[87]

20.
Katharine McPhee
(season 5, runner-up)
475,000[52]

Katharine McPhee (2007) #2 — 381,000[26]
Unbroken (2010) #27 — 45,000[26]
Christmas Is the Time…To Say I Love You (2010) did not chart — 23,000[26]
Hysteria (2015) did not chart

21.
Lauren Alaina
(season 10, runner-up)
454,000[52]

Wildflower (2011) #5 — 303,000[88]
Road Less Traveled (2016) #31 — 29,100[89]

22.
Bucky Covington
(season 5, 8th place)
did not chart
436,000

Bucky Covington (2007) #4 — 433,000[56]
Good Guys (2012) #178 — 3,000[90]

23.
Blake Lewis
(season 6, runner-up)
413,000[56]

A.D.D. (Audio Day Dream) (2007) #10 — 350,000[91]
Heartbreak on Vinyl (2009) #135 — 10,000[92]
Portrait of a Chameleon (2013) did not chart — 2,000[93]

24.
Kris Allen
(season 8, winner)
401,600

Kris Allen (2009) #11 — 346,000[94]
Thank You Camellia (2012) #26 — 35,000[95]
Horizons (2014) #80 — 4,000[96]
Letting You In (2016)

25.
William Hung
(Season 3, Auditioner)
242,000

Inspiration (2004) #34 — 200,000[97]
Hung for the Holidays (2004) did not chart — 35,000[98]
Miracle: Happy Summer from William Hung (2005) did not chart — 7,000[98]

26.
Kimberley Locke
(season 2, 3rd place)
241,000[56]

One Love (2004) #16 — 212,000[99]
Based on a True Story (2007) #160 — 22,000[100]
Christmas (2008) did not chart — 3,000[75]

27.
Crystal Bowersox
(season 9, runner-up)
230,000[56]

Farmer's Daughter (2010) #28 — 205,000 [101]
All That For This (2013) #71 — 8,000[68]

28.
Danny Gokey
(season 8, 3rd place)
204,000

My Best Days (2010) #4 — 204,000[102]
Hope in Front of Me (2014) #40

29.
James Durbin
(season 10, 4th place)
192,000

Memories of a Beautiful Disaster (2011) #36 — 121,000[103]
Celebrate (2014) #83

30.
Lee DeWyze
(season 9, winner)
178,000

Live It Up (2010) #19 — 153,000[104]
Frames (2013) #116 — 3,000[105]
Oil & Water (2016)

31.
Diana DeGarmo
(Season 3, Runner-Up)
168,000[106]

Blue Skies (2004) #52

32.
Justin Guarini
(season 1, runner-up)
146,000

Justin Guarini (2003) #20 — 146,000[53]
Stranger Things Have Happened (2005) did not chart

33.
Haley Reinhart
(season 10, 3rd place)
143,500

Listen Up! (2012) #17 —77,000[107]
Better (2016) did not chart — 7,500[108]

34.
Colton Dixon
(season 11, 7th place)
128,000

A Messenger (2013) #15 — 100,000[109]
Anchor (2014) #23 — 28,000[47]
The Calm Before the Storm (2015) did not chart

35.
Tamyra Gray
(season 1, 4th place)
123,000[99]

The Dreamer (2004) #23

36.
Jason Castro
(Season 7, 4th Place)
105,000

Jason Castro (2010) #18 — 54,000[110]
Who I Am (2010) #198 — 18,000[111]
Only a Mountain (2013) did not chart — 20,000[112]

37.
Allison Iraheta
(Season 8, 4th Place)
103,000[113]

Just Like You (2009) #35

38.
Melinda Doolittle
(season 6, 3rd place)
091,000[114]

Coming Back to You (2009) #58

39.
Casey James
(season 9, 3rd place)
077,000[38]

Casey James (2012) #23

40.
Chris Sligh
(season 6, 10th place)
064,000

Running Back to You (2008) #190 — 54,000[115]
The Anatomy of Broken (2010) did not chart — 10,000[116]

41.
LaToya London
(Season 3, 4th Place)
058,000[99]

Love & Life (2005) #82

42.
Phil Stacey
(season 6, 6th place)
058,000

Phil Stacey (2008) #43 — 40,000 [80]
Into the Light (2009) did not chart — 18,000[76]

43.
Mario Vazquez
(season 4, Top 12)
056,000[117]

Mario Vazquez (2006) #80

44.
George Huff
(season 3, 5th place)
52,000

Miracles (2005) did not chart — 29,000 [99]
George Huff (2009) did not chart — 4,000 [114]

45.
Brooke White
(season 7, 5th place)
048,000[118]

High Hopes & Heartbreak (2009) #50 — 29,000[114]
Gemini (2011) did not chart — 2,000[119]

46.
Carly Smithson
(as a part of We Are the Fallen)
(Season 7, 6th Place)
041,000[120]

Tear the World Down (2010) #33

47.
Jessica Sanchez
(Season 11, Runnerup)
38,000

Me, You & the Music (2013) #26 — 17,000[109]

48.
Kristy Lee Cook
(season 7, 7th place)
032,000[121]

Why Wait (2008) #49

49.
Candice Glover
(Season 12, Winner)
027,000[122]

Music Speaks (2014) #14

50.
Casey Abrams
(season 10, 6th place)
27,000[123]

Casey Abrams (2012) #101

51.
Constantine Maroulis
(season 4, 6th place)
25,000[124]

Constantine (2007) #75

52.
Caleb Johnson
(season 13, winner)
024,000[125]

Testify (2014) #24

53.
Paris Bennett
(season 5, 5th place)
22,300

Princess P (2007) #133 — 22,000 [126]
A Royal Christmas (2008) did not chart — 300 [75]

54.
R. J. Helton
(season 1, 5th place)
022,000[99]

Real Life (2004) did not chart

55.
John Stevens
(Season 3, 6th Place)
021,000[99]

Red (2005) did not chart

56.
Michael Johns
(season 7, 8th place)
020,000[114]

Hold Back My Heart (2009) #97

57.
Jasmine Trias
(season 3, 3rd place)
014,000[99]

Jasmine Trias (2005) did not chart

58.
Ace Young
(season 5, 7th place)
010,000[75]

Ace Young (2008) #160

59.
LaKisha Jones
(season 6, 4th place)
007,000[114]

So Glad I'm Me (2009) did not chart

60.
Nick Fradiani
(season 14, winner)
005,000[127]

Hurricane (2016) #121

61.
Danny Noriega
(season 7, semi)
005,000[128]

Till Death Do Us Party (2014) #59

62.
Jim Verraros
(season 1, 9th place)
004,300[99]

Rollercoaster (2005) did not chart
Do Not Disturb (2011) did not chart

63.
Carmen Rasmusen
(season 2, 6th place)
003,100[99]

Nothin' Like the Summer (2007) did not chart

64.
Kimberly Caldwell
(season 2, 7th place)
003,000[85]

Without Regret (2011) did not chart

65.
Ayla Brown
(season 5, Top 16)
003,000[129]

Forward (2006) did not chart

66.
Corey Clark
(season 2, 9th place)
002,600[99]

Corey Clark (2005) did not chart

67.
Tim Halperin
(Season 10, Semifinal)
002,000[130]

Rise and Fall (2011) did not chart

68.
Jon Peter Lewis
(Season 3, 8th Place)
001,600

Stories from Hollywood (2006) did not chart — 1,100[99]
Break the Silence (2008) did not chart — 500[131]

69.
Michael Sarver
(season 8, 10th place)
001,000[132]

Michael Sarver (2010) did not chart

70.
Josiah Leming
(season 7, Hollywood round)
001,000[76]

Come On Kid (2010) did not chart

71.
Kree Harrison
(season 12, 2nd place)
000900[133]

This Old Thing (2016) did not chart