Atomic Masses

Atomic Masses

Atomic Number, ZNameAtomic Mass Number, ASymbolAtomic Mass (u)Percent Abundance or Decay ModeHalf-life, t1/2
0neutron1 1.008 665 10.37 min
1Hydrogen1 1.007 82599.985% 
 Deuterium2 2.014 1020.015% 
 Tritium3 3.016 050 12.33 y
2Helium3 3.016 030  
  4 4.002 603  
3Lithium6 6.015 1217.5% 
  7 7.016 00392.5% 
4Beryllium7 7.016 928EC53.29 d
  9 9.012 182100% 
5Boron10 10.012 93719.9% 
  11 11.009 30580.1% 
6Carbon11 11.011 432EC, 
  12 12.000 00098.90% 
  13 13.003 3551.10% 
  14 14.003 241 5730 y
7Nitrogen13 13.005 738 9.96 min
  14 14.003 07499.63% 
  15 15.000 1080.37% 
8Oxygen15 15.003 065EC,122 s
  16 15.994 91599.76% 
  18 17.999 1600.200% 
9Fluorine18 18.000 937EC,1.83 h
  19 18.998 403100% 
10Neon20 19.992 43590.51% 
  22 21.991 3839.22% 
11Sodium22 21.994 434 2.602 y
  23 22.989 767100% 
  24 23.990 961 14.96 h
12Magnesium24 23.985 04278.99% 
13Aluminum27 26.981 539100% 
14Silicon28 27.976 92792.23%2.62h
  31 30.975 362  
15Phosphorus31 30.973 762100% 
  32 31.973 907 14.28 d
16Sulfur32 31.972 07095.02% 
  35 34.969 031 87.4 d
17Chlorine35 34.968 85275.77% 
  37 36.965 90324.23% 
18Argon40 39.962 38499.60% 
19Potassium39 38.963 70793.26% 
  40 39.963 9990.0117%, EC, 
20Calcium40 39.962 59196.94% 
21Scandium45 44.955 910100% 
22Titanium48 47.947 94773.8% 
23Vanadium51 50.943 96299.75% 
24Chromium52 51.940 50983.79% 
25Manganese55 54.938 047100% 
26Iron56 55.934 93991.72% 
27Cobalt59 58.933 198100% 
  60 59.933 819 5.271 y
28Nickel58 57.935 34668.27% 
  60 59.930 78826.10% 
29Copper63 62.939 59869.17% 
  65 64.927 79330.83% 
30Zinc64 63.929 14548.6% 
  66 65.926 03427.9% 
31Gallium69 68.925 58060.1% 
32Germanium72 71.922 07927.4% 
  74 73.921 17736.5% 
33Arsenic75 74.921 594100% 
34Selenium80 79.916 52049.7% 
35Bromine79 78.918 33650.69% 
36Krypton84 83.911 50757.0% 
37Rubidium85 84.911 79472.17% 
38Strontium86 85.909 2679.86% 
  88 87.905 61982.58% 
  90 89.907 738­28.8 y
39Yttrium89 88.905 849100% 
  90 89.907 152­64.1 h
40Zirconium90 89.904 70351.45% 
41Niobium93 92.906 377100% 
42Molybdenum98 97.905 40624.13% 
43Technetium98 97.907 215­ 
44Ruthenium102 101.904 34831.6% 
45Rhodium103 102.905 500100% 
46Palladium106 105.903 47827.33% 
47Silver107 106.905 09251.84% 
  109 108.904 75748.16% 
48Cadmium114 113.903 35728.73% 
49Indium115 114.903 88095.7%, ­ 
50Tin120 119.902 20032.59% 
51Antimony121 120.903 82157.3% 
52Tellurium130 129.906 22933.8%, ­ 
53Iodine127 126.904 473100% 
  131 130.906 114­8.040 d
54Xenon132 131.904 14426.9% 
  136 135.907 2148.9% 
55Cesium133 132.905 429100% 
  134 133.906 696EC, ­2.06 y
56Barium137 136.905 81211.23% 
  138 137.905 23271.70% 
57Lanthanum139 138.906 34699.91% 
58Cerium140 139.905 43388.48% 
59Praseodymium141 140.907 647100% 
60Neodymium142 141.907 71927.13% 
61Promethium145 144.912 743EC,17.7 y
62Samarium152 151.919 72926.7% 
63Europium153 152.921 22552.2% 
64Gadolinium158 157.924 09924.84% 
65Terbium159 158.925 342100% 
66Dysprosium164 163.929 17128.2% 
67Holmium165 164.930 319100% 
68Erbium166 165.930 29033.6% 
69Thulium169 168.934 212100% 
70Ytterbium174 173.938 85931.8% 
71Lutecium175 174.940 77097.41% 
72Hafnium180 179.946 54535.10% 
73Tantalum181 180.947 99299.98% 
74Tungsten184 183.950 92830.67% 
75Rhenium187 186.955 74462.6%, 
76Osmium191 190.960 920­15.4 d
  192 191.961 46741.0% 
77Iridium191 190.960 58437.3% 
  193 192.962 91762.7% 
78Platinum195 194.964 76633.8% 
79Gold197 196.966 543100% 
  198 197.968 217­2.696 d
80Mercury199 198.968 25316.87% 
  202 201.970 61729.86% 
81Thallium205 204.974 40170.48% 
82Lead206 205.974 44024.1% 
  207 206.975 87222.1% 
  208 207.976 62752.4% 
  210 209.984 163­22.3 y
  211 210.988 735­36.1 min
  212 211.991 871­10.64 h
83Bismuth209 208.980 374100% 
  211 210.987 255 2.14 min
84Polonium210 209.982 848 138.38 d
85Astatine218 218.008 684 1.6 s
86Radon222 222.017 570 3.82 d
87Francium223 223.019 733 21.8 min
88Radium226 226.025 402  
89Actinium227 227.027 750 21.8 y
90Thorium228 228.028 715 1.91 y
  232 232.038 054100%, 
91Protactinium231 231.035 880  
92Uranium233 233.039 628  
  235 235.043 9240.720%, 
  236 236.045 562  
  238 238.050 78499.2745%, 
  239 239.054 289­23.5 min
93Neptunium239 239.052 933­2.355 d
94Plutonium239 239.052 157  
95Americium243 243.061 375fission 
96Curium245 245.065 483  
97Berkelium247 247.070 300  
98Californium249 249.074 844 351 y
99Einsteinium254 254.088 019­276 d
100Fermium253 253.085 173EC,3.00 d
101Mendelevium255 255.091 081EC,27 min
102Nobelium255 255.093 260EC,3.1 min
103Lawrencium257 257.099 480EC,0.646 s
104Rutherfordium261 261.108 690 1.08 min
105Dubnium262 262.113 760fission34 s
106Seaborgium263 263.11 86fission0.8 s
107Bohrium262 262.123 1 0.102 s
108Hassium264 264.128 5 0.08 ms
109Meitnerium266 266.137 8 3.4 ms

[Attributions and Licenses]


This is a lesson from the tutorial, Radioactivity and Nuclear Physics and you are encouraged to log in or register, so that you can track your progress.

Log In

Share Thoughts