Column Descriptions
Relative Isotopic Standard
Isotope Atomic Mass Composition Atomic Weight Notes
_________________________________________________________________________
1 H 1 1.00782503223(9) 0.999885(70) [1.00784,1.00811] m
D 2 2.01410177812(12) 0.000115(70)
T 3 3.0160492779(24)
_________________________________________________________________________
2 He 3 3.0160293201(25) 0.00000134(3) 4.002602(2) g,r
4 4.00260325413(6) 0.99999866(3)
_________________________________________________________________________
3 Li 6 6.0151228874(16) 0.0759(4) [6.938,6.997] m
7 7.0160034366(45) 0.9241(4)
_________________________________________________________________________
4 Be 9 9.012183065(82) 1 9.0121831(5)
_________________________________________________________________________
5 B 10 10.01293695(41) 0.199(7) [10.806,10.821] m
11 11.00930536(45) 0.801(7)
_________________________________________________________________________
6 C 12 12.0000000(00) 0.9893(8) [12.0096,12.0116]
13 13.00335483507(23) 0.0107(8)
14 14.0032419884(40)
_________________________________________________________________________
7 N 14 14.00307400443(20) 0.99636(20) [14.00643,14.00728]
15 15.00010889888(64) 0.00364(20)
_________________________________________________________________________
8 O 16 15.99491461957(17) 0.99757(16) [15.99903,15.99977]
17 16.99913175650(69) 0.00038(1)
18 17.99915961286(76) 0.00205(14)
_________________________________________________________________________
9 F 19 18.99840316273(92) 1 18.998403163(6)
_________________________________________________________________________
10 Ne 20 19.9924401762(17) 0.9048(3) 20.1797(6) g,m
21 20.993846685(41) 0.0027(1)
22 21.991385114(18) 0.0925(3)
_________________________________________________________________________
11 Na 23 22.9897692820(19) 1 22.98976928(2)
_________________________________________________________________________
12 Mg 24 23.985041697(14) 0.7899(4) [24.304,24.307]
25 24.985836976(50) 0.1000(1)
26 25.982592968(31) 0.1101(3)
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13 Al 27 26.98153853(11) 1 26.9815385(7)
_________________________________________________________________________
14 Si 28 27.97692653465(44) 0.92223(19) [28.084,28.086]
29 28.97649466490(52) 0.04685(8)
30 29.973770136(23) 0.03092(11)
_________________________________________________________________________
15 P 31 30.97376199842(70) 1 30.973761998(5)
_________________________________________________________________________
16 S 32 31.9720711744(14) 0.9499(26) [32.059,32.076]
33 32.9714589098(15) 0.0075(2)
34 33.967867004(47) 0.0425(24)
36 35.96708071(20) 0.0001(1)
_________________________________________________________________________
17 Cl 35 34.968852682(37) 0.7576(10) [35.446,35.457] m
37 36.965902602(55) 0.2424(10)
_________________________________________________________________________
18 Ar 36 35.967545105(28) 0.003336(21) 39.948(1) g,r
38 37.96273211(21) 0.000629(7)
40 39.9623831237(24) 0.996035(25)
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19 K 39 38.9637064864(49) 0.932581(44) 39.0983(1)
40 39.963998166(60) 0.000117(1)
41 40.9618252579(41) 0.067302(44)
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20 Ca 40 39.962590863(22) 0.96941(156) 40.078(4) g
42 41.95861783(16) 0.00647(23)
43 42.95876644(24) 0.00135(10)
44 43.95548156(35) 0.02086(110)
46 45.9536890(24) 0.00004(3)
48 47.95252276(13) 0.00187(21)
_________________________________________________________________________
21 Sc 45 44.95590828(77) 1 44.955908(5)
_________________________________________________________________________
22 Ti 46 45.95262772(35) 0.0825(3) 47.867(1)
47 46.95175879(38) 0.0744(2)
48 47.94794198(38) 0.7372(3)
49 48.94786568(39) 0.0541(2)
50 49.94478689(39) 0.0518(2)
_________________________________________________________________________
23 V 50 49.94715601(95) 0.00250(4) 50.9415(1)
51 50.94395704(94) 0.99750(4)
_________________________________________________________________________
24 Cr 50 49.94604183(94) 0.04345(13) 51.9961(6)
52 51.94050623(63) 0.83789(18)
53 52.94064815(62) 0.09501(17)
54 53.93887916(61) 0.02365(7)
_________________________________________________________________________
25 Mn 55 54.93804391(48) 1 54.938044(3)
_________________________________________________________________________
26 Fe 54 53.93960899(53) 0.05845(35) 55.845(2)
56 55.93493633(49) 0.91754(36)
57 56.93539284(49) 0.02119(10)
58 57.93327443(53) 0.00282(4)
_________________________________________________________________________
27 Co 59 58.93319429(56) 1 58.933194(4)
_________________________________________________________________________
28 Ni 58 57.93534241(52) 0.68077(19) 58.6934(4) r
60 59.93078588(52) 0.26223(15)
61 60.93105557(52) 0.011399(13)
62 61.92834537(55) 0.036346(40)
64 63.92796682(58) 0.009255(19)
_________________________________________________________________________
29 Cu 63 62.92959772(56) 0.6915(15) 63.546(3) r
65 64.92778970(71) 0.3085(15)
_________________________________________________________________________
30 Zn 64 63.92914201(71) 0.4917(75) 65.38(2) r
66 65.92603381(94) 0.2773(98)
67 66.92712775(96) 0.0404(16)
68 67.92484455(98) 0.1845(63)
70 69.9253192(21) 0.0061(10)
_________________________________________________________________________
31 Ga 69 68.9255735(13) 0.60108(9) 69.723(1)
71 70.92470258(87) 0.39892(9)
_________________________________________________________________________
32 Ge 70 69.92424875(90) 0.2057(27) 72.630(8)
72 71.922075826(81) 0.2745(32)
73 72.923458956(61) 0.0775(12)
74 73.921177761(13) 0.3650(20)
76 75.921402726(19) 0.0773(12)
_________________________________________________________________________
33 As 75 74.92159457(95) 1 74.921595(6)
_________________________________________________________________________
34 Se 74 73.922475934(15) 0.0089(4) 78.971(8) r
76 75.919213704(17) 0.0937(29)
77 76.919914154(67) 0.0763(16)
78 77.91730928(20) 0.2377(28)
80 79.9165218(13) 0.4961(41)
82 81.9166995(15) 0.0873(22)
_________________________________________________________________________
35 Br 79 78.9183376(14) 0.5069(7) [79.901,79.907]
81 80.9162897(14) 0.4931(7)
_________________________________________________________________________
36 Kr 78 77.92036494(76) 0.00355(3) 83.798(2) g,m
80 79.91637808(75) 0.02286(10)
82 81.91348273(94) 0.11593(31)
83 82.91412716(32) 0.11500(19)
84 83.9114977282(44) 0.56987(15)
86 85.9106106269(41) 0.17279(41)
_________________________________________________________________________
37 Rb 85 84.9117897379(54) 0.7217(2) 85.4678(3) g
87 86.9091805310(60) 0.2783(2)
_________________________________________________________________________
38 Sr 84 83.9134191(13) 0.0056(1) 87.62(1) g,r
86 85.9092606(12) 0.0986(1)
87 86.9088775(12) 0.0700(1)
88 87.9056125(12) 0.8258(1)
_________________________________________________________________________
39 Y 89 88.9058403(24) 1 88.90584(2)
_________________________________________________________________________
40 Zr 90 89.9046977(20) 0.5145(40) 91.224(2) g
91 90.9056396(20) 0.1122(5)
92 91.9050347(20) 0.1715(8)
94 93.9063108(20) 0.1738(28)
96 95.9082714(21) 0.0280(9)
_________________________________________________________________________
41 Nb 93 92.9063730(20) 1 92.90637(2)
_________________________________________________________________________
42 Mo 92 91.90680796(84) 0.1453(30) 95.95(1) g
94 93.90508490(48) 0.0915(9)
95 94.90583877(47) 0.1584(11)
96 95.90467612(47) 0.1667(15)
97 96.90601812(49) 0.0960(14)
98 97.90540482(49) 0.2439(37)
100 99.9074718(11) 0.0982(31)
_________________________________________________________________________
43 Tc 97 96.9063667(40) [98]
98 97.9072124(36)
99 98.9062508(10)
_________________________________________________________________________
44 Ru 96 95.90759025(49) 0.0554(14) 101.07(2) g
98 97.9052868(69) 0.0187(3)
99 98.9059341(11) 0.1276(14)
100 99.9042143(11) 0.1260(7)
101 100.9055769(12) 0.1706(2)
102 101.9043441(12) 0.3155(14)
104 103.9054275(28) 0.1862(27)
_________________________________________________________________________
45 Rh 103 102.9054980(26) 1 102.90550(2)
_________________________________________________________________________
46 Pd 102 101.9056022(28) 0.0102(1) 106.42(1) g
104 103.9040305(14) 0.1114(8)
105 104.9050796(12) 0.2233(8)
106 105.9034804(12) 0.2733(3)
108 107.9038916(12) 0.2646(9)
110 109.90517220(75) 0.1172(9)
_________________________________________________________________________
47 Ag 107 106.9050916(26) 0.51839(8) 107.8682(2) g
109 108.9047553(14) 0.48161(8)
_________________________________________________________________________
48 Cd 106 105.9064599(12) 0.0125(6) 112.414(4) g
108 107.9041834(12) 0.0089(3)
110 109.90300661(61) 0.1249(18)
111 110.90418287(61) 0.1280(12)
112 111.90276287(60) 0.2413(21)
113 112.90440813(45) 0.1222(12)
114 113.90336509(43) 0.2873(42)
116 115.90476315(17) 0.0749(18)
_________________________________________________________________________
49 In 113 112.90406184(91) 0.0429(5) 114.818(1)
115 114.903878776(12) 0.9571(5)
_________________________________________________________________________
50 Sn 112 111.90482387(61) 0.0097(1) 118.710(7) g
114 113.9027827(10) 0.0066(1)
115 114.903344699(16) 0.0034(1)
116 115.90174280(10) 0.1454(9)
117 116.90295398(52) 0.0768(7)
118 117.90160657(54) 0.2422(9)
119 118.90331117(78) 0.0859(4)
120 119.90220163(97) 0.3258(9)
122 121.9034438(26) 0.0463(3)
124 123.9052766(11) 0.0579(5)
_________________________________________________________________________
51 Sb 121 120.9038120(30) 0.5721(5) 121.760(1) g
123 122.9042132(23) 0.4279(5)
_________________________________________________________________________
52 Te 120 119.9040593(33) 0.0009(1) 127.60(3) g
122 121.9030435(16) 0.0255(12)
123 122.9042698(16) 0.0089(3)
124 123.9028171(16) 0.0474(14)
125 124.9044299(16) 0.0707(15)
126 125.9033109(16) 0.1884(25)
128 127.90446128(93) 0.3174(8)
130 129.906222748(12) 0.3408(62)
_________________________________________________________________________
53 I 127 126.9044719(39) 1 126.90447(3)
_________________________________________________________________________
54 Xe 124 123.9058920(19) 0.000952(3) 131.293(6) g,m
126 125.9042983(38) 0.000890(2)
128 127.9035310(11) 0.019102(8)
129 128.9047808611(60) 0.264006(82)
130 129.903509349(10) 0.040710(13)
131 130.90508406(24) 0.212324(30)
132 131.9041550856(56) 0.269086(33)
134 133.90539466(90) 0.104357(21)
136 135.907214484(11) 0.088573(44)
_________________________________________________________________________
55 Cs 133 132.9054519610(80) 1 132.90545196(6)
_________________________________________________________________________
56 Ba 130 129.9063207(28) 0.00106(1) 137.327(7)
132 131.9050611(11) 0.00101(1)
134 133.90450818(30) 0.02417(18)
135 134.90568838(29) 0.06592(12)
136 135.90457573(29) 0.07854(24)
137 136.90582714(30) 0.11232(24)
138 137.90524700(31) 0.71698(42)
_________________________________________________________________________
57 La 138 137.9071149(37) 0.0008881(71) 138.90547(7) g
139 138.9063563(24) 0.9991119(71)
_________________________________________________________________________
58 Ce 136 135.90712921(41) 0.00185(2) 140.116(1) g
138 137.905991(11) 0.00251(2)
140 139.9054431(23) 0.88450(51)
142 141.9092504(29) 0.11114(51)
_________________________________________________________________________
59 Pr 141 140.9076576(23) 1 140.90766(2)
_________________________________________________________________________
60 Nd 142 141.9077290(20) 0.27152(40) 144.242(3) g
143 142.9098200(20) 0.12174(26)
144 143.9100930(20) 0.23798(19)
145 144.9125793(20) 0.08293(12)
146 145.9131226(20) 0.17189(32)
148 147.9168993(26) 0.05756(21)
150 149.9209022(18) 0.05638(28)
_________________________________________________________________________
61 Pm 145 144.9127559(33) [145]
147 146.9151450(19)
_________________________________________________________________________
62 Sm 144 143.9120065(21) 0.0307(7) 150.36(2) g
147 146.9149044(19) 0.1499(18)
148 147.9148292(19) 0.1124(10)
149 148.9171921(18) 0.1382(7)
150 149.9172829(18) 0.0738(1)
152 151.9197397(18) 0.2675(16)
154 153.9222169(20) 0.2275(29)
_________________________________________________________________________
63 Eu 151 150.9198578(18) 0.4781(6) 151.964(1) g
153 152.9212380(18) 0.5219(6)
_________________________________________________________________________
64 Gd 152 151.9197995(18) 0.0020(1) 157.25(3) g
154 153.9208741(17) 0.0218(3)
155 154.9226305(17) 0.1480(12)
156 155.9221312(17) 0.2047(9)
157 156.9239686(17) 0.1565(2)
158 157.9241123(17) 0.2484(7)
160 159.9270624(18) 0.2186(19)
_________________________________________________________________________
65 Tb 159 158.9253547(19) 1 158.92535(2)
_________________________________________________________________________
66 Dy 156 155.9242847(17) 0.00056(3) 162.500(1) g
158 157.9244159(31) 0.00095(3)
160 159.9252046(20) 0.02329(18)
161 160.9269405(20) 0.18889(42)
162 161.9268056(20) 0.25475(36)
163 162.9287383(20) 0.24896(42)
164 163.9291819(20) 0.28260(54)
_________________________________________________________________________
67 Ho 165 164.9303288(21) 1 164.93033(2)
_________________________________________________________________________
68 Er 162 161.9287884(20) 0.00139(5) 167.259(3) g
164 163.9292088(20) 0.01601(3)
166 165.9302995(22) 0.33503(36)
167 166.9320546(22) 0.22869(9)
168 167.9323767(22) 0.26978(18)
170 169.9354702(26) 0.14910(36)
_________________________________________________________________________
69 Tm 169 168.9342179(22) 1 168.93422(2)
_________________________________________________________________________
70 Yb 168 167.9338896(22) 0.00123(3) 173.054(5) g
170 169.9347664(22) 0.02982(39)
171 170.9363302(22) 0.1409(14)
172 171.9363859(22) 0.2168(13)
173 172.9382151(22) 0.16103(63)
174 173.9388664(22) 0.32026(80)
176 175.9425764(24) 0.12996(83)
_________________________________________________________________________
71 Lu 175 174.9407752(20) 0.97401(13) 174.9668(1) g
176 175.9426897(20) 0.02599(13)
_________________________________________________________________________
72 Hf 174 173.9400461(28) 0.0016(1) 178.49(2)
176 175.9414076(22) 0.0526(7)
177 176.9432277(20) 0.1860(9)
178 177.9437058(20) 0.2728(7)
179 178.9458232(20) 0.1362(2)
180 179.9465570(20) 0.3508(16)
_________________________________________________________________________
73 Ta 180 179.9474648(24) 0.0001201(32) 180.94788(2)
181 180.9479958(20) 0.9998799(32)
_________________________________________________________________________
74 W 180 179.9467108(20) 0.0012(1) 183.84(1)
182 181.94820394(91) 0.2650(16)
183 182.95022275(90) 0.1431(4)
184 183.95093092(94) 0.3064(2)
186 185.9543628(17) 0.2843(19)
_________________________________________________________________________
75 Re 185 184.9529545(13) 0.3740(2) 186.207(1)
187 186.9557501(16) 0.6260(2)
_________________________________________________________________________
76 Os 184 183.9524885(14) 0.0002(1) 190.23(3) g
186 185.9538350(16) 0.0159(3)
187 186.9557474(16) 0.0196(2)
188 187.9558352(16) 0.1324(8)
189 188.9581442(17) 0.1615(5)
190 189.9584437(17) 0.2626(2)
192 191.9614770(29) 0.4078(19)
_________________________________________________________________________
77 Ir 191 190.9605893(21) 0.373(2) 192.217(3)
193 192.9629216(21) 0.627(2)
_________________________________________________________________________
78 Pt 190 189.9599297(63) 0.00012(2) 195.084(9)
192 191.9610387(32) 0.00782(24)
194 193.9626809(10) 0.3286(40)
195 194.9647917(10) 0.3378(24)
196 195.96495209(99) 0.2521(34)
198 197.9678949(23) 0.07356(130)
_________________________________________________________________________
79 Au 197 196.96656879(71) 1 196.966569(5)
_________________________________________________________________________
80 Hg 196 195.9658326(32) 0.0015(1) 200.592(3)
198 197.96676860(52) 0.0997(20)
199 198.96828064(46) 0.1687(22)
200 199.96832659(47) 0.2310(19)
201 200.97030284(69) 0.1318(9)
202 201.97064340(69) 0.2986(26)
204 203.97349398(53) 0.0687(15)
_________________________________________________________________________
81 Tl 203 202.9723446(14) 0.2952(1) [204.382,204.385]
205 204.9744278(14) 0.7048(1)
_________________________________________________________________________
82 Pb 204 203.9730440(13) 0.014(1) 207.2(1) g,r
206 205.9744657(13) 0.241(1)
207 206.9758973(13) 0.221(1)
208 207.9766525(13) 0.524(1)
_________________________________________________________________________
83 Bi 209 208.9803991(16) 1 208.98040(1)
_________________________________________________________________________
84 Po 209 208.9824308(20) [209]
210 209.9828741(13)
_________________________________________________________________________
85 At 210 209.9871479(83) [210]
211 210.9874966(30)
_________________________________________________________________________
86 Rn 211 210.9906011(73) [222]
220 220.0113941(23)
222 222.0175782(25)
_________________________________________________________________________
87 Fr 223 223.0197360(25) [223]
_________________________________________________________________________
88 Ra 223 223.0185023(27) [226]
224 224.0202120(23)
226 226.0254103(25)
228 228.0310707(26)
_________________________________________________________________________
89 Ac 227 227.0277523(25) [227]
_________________________________________________________________________
90 Th 230 230.0331341(19) 232.0377(4) g
232 232.0380558(21) 1
_________________________________________________________________________
91 Pa 231 231.0358842(24) 1 231.03588(2)
_________________________________________________________________________
92 U 233 233.0396355(29) 238.02891(3) g,m
234 234.0409523(19) 0.000054(5)
235 235.0439301(19) 0.007204(6)
236 236.0455682(19)
238 238.0507884(20) 0.992742(10)
_________________________________________________________________________
93 Np 236 236.046570(54) [237]
237 237.0481736(19)
_________________________________________________________________________
94 Pu 238 238.0495601(19) [244]
239 239.0521636(19)
240 240.0538138(19)
241 241.0568517(19)
242 242.0587428(20)
244 244.0642053(56)
_________________________________________________________________________
95 Am 241 241.0568293(19)
243 243.0613813(24)
_________________________________________________________________________
96 Cm 243 243.0613893(22)
244 244.0627528(19)
245 245.0654915(22)
246 246.0672238(22)
247 247.0703541(47)
248 248.0723499(56)
_________________________________________________________________________
97 Bk 247 247.0703073(59)
249 249.0749877(27)
_________________________________________________________________________
98 Cf 249 249.0748539(23)
250 250.0764062(22)
251 251.0795886(48)
252 252.0816272(56)
_________________________________________________________________________
99 Es 252 252.082980(54)
_________________________________________________________________________
100 Fm 257 257.0951061(69)
_________________________________________________________________________
101 Md 258 258.0984315(50)
260 260.10365(34#)
_________________________________________________________________________
102 No 259 259.10103(11#)
_________________________________________________________________________
103 Lr 262 262.10961(22#)
_________________________________________________________________________
104 Rf 267 267.12179(62#)
_________________________________________________________________________
105 Db 268 268.12567(57#)
_________________________________________________________________________
106 Sg 271 271.13393(63#)
_________________________________________________________________________
107 Bh 272 272.13826(58#)
_________________________________________________________________________
108 Hs 270 270.13429(27#)
_________________________________________________________________________
109 Mt 276 276.15159(59#)
_________________________________________________________________________
110 Ds 281 281.16451(59#)
_________________________________________________________________________
111 Rg 280 280.16514(61#)
_________________________________________________________________________
112 Cn 285 285.17712(60#)
_________________________________________________________________________
113 Nh 284 284.17873(62#)
_________________________________________________________________________
114 Fl 289 289.19042(60#)
_________________________________________________________________________
115 Mc 288 288.19274(62#)
_________________________________________________________________________
116 Lv 293 293.20449(60#)
_________________________________________________________________________
117 Ts 292 292.20746(75#)
_________________________________________________________________________
118 Og 294 294.21392(71#)
_________________________________________________________________________
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