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A4: Masses of Selected Isotopes

Isotope Mass (amu) Isotope Mass (amu) Isotope Mass (amu)
1H 1.007825 14N 14.003074 208Po 207.981246
2H 2.014102 16O 15.994915 210Po 209.982874
3H 3.016049 52Cr 51.940508 222Rn 222.017578
3He 3.016029 56Fe 55.934938 226Ra 226.025410
4He 4.002603 59Co 58.933195 230Th 230.033134
6Li 6.015123 58Ni 57.935343 234Th 234.043601
7Li 7.016005 60Ni 59.930786 234Pa 234.043308
9Be 9.012182 90Rb 89.914802 233U 233.039635
10B 10.012937 144Cs 143.932077 234U 234.040952
11B 11.009305 206Pb 205.974465 235U 235.043930
12C 12 207Pb 206.975897 238U 238.050788
13C 13.003355 208Pb 207.976652 239Pu 239.052163
14C 14.003242        
Isotope Mass (amu) Isotope Mass (amu)
8B 8.024607 209Fr 208.99592
40K 39.963998 210Po 209.982874
52Cr 51.940508 212At 211.990745
58Ni 57.935343 214Pb 213.999797
59Co 58.933195 214Bi 213.998712
60Co 59.933817 216Fr 216.003198
60Ni 59.930786 199Pb 198.972917
90Sr 89.907738 222Rn 222.017578
92Kr 91.926156 226Ra 226.025410
141Ba 140.914411 227Ra 227.029178
143Xe 142.935110 228Ac 228.031021
167Os 166.971550 230Th 230.033134
171Pt 170.981240 233U 233.039635
194Hg 193.965439 234Th 234.043601
194Tl 193.971200 234Pa 234.043308
199Pb 198.972917 233U 233.039635
199Bi 198.977672 234U 234.040952
206Pb 205.974465 235U 235.043930
207Pb 206.975897 238Pa 238.054500
208Pb 207.976652 238U 238.050788
208Bi 207.979742 239Pu 239.052163
208Po 207.981246 245Pu 245.067747

Data source: G. Audi, A. H. Wapstra, and C. Thibault, The AME2003 atomic mass evaluation.