| Isotope | | Relative
Atomic Mass | | Isotopic
Composition | Standard
Atomic Weight | Notes |
|---|
|
 | | | | | | | 1 | H | 1 | 1.007 825 032 1(4) | 99.9885(70) | 1.007 94(7) | g,m,r,c,w | | D | 2 | 2.014 101 778 0(4) | 0.0115(70) | | T | 3 | 3.016 049 2675(11) | |
| | 2 | He | 3 | 3.016 029 309 7(9) | 0.000 137(3) | 4.002 602(2) | g,r,a | | 4 | 4.002 603 2497(10) | 99.999 863(3) |
| | 3 | Li | 6 | 6.015 122 3(5) | 7.59(4) | 6.941(2) | g,m,r,b,d | | 7 | 7.016 004 0(5) | 92.41(4) |
| | 4 | Be | 9 | 9.012 182 1(4) | 100 | 9.012 182(3) | |
| | 5 | B | 10 | 10.012 937 0(4) | 19.9(7) | 10.811(7) | g,m,r | | 11 | 11.009 305 5(5) | 80.1(7) | 
| | 6 | C | 12 | 12.000 000 0(0) | 98.93(8) | 12.0107(8) | g,r | | 13 | 13.003 354 8378(10) | 1.07(8) | | 14 | 14.003 241 988(4) | |
| | 7 | N | 14 | 14.003 074 005 2(9) | 99.632(7) | 14.0067(2) | g,r,e | | 15 | 15.000 108 898 4(9) | 0.368(7) |
| | 8 | O | 16 | 15.994 914 6221(15) | 99.757(16) | 15.9994(3) | g,r | | 17 | 16.999 131 50(22) | 0.038(1) | | 18 | 17.999 160 4(9) | 0.205(14) |
| | 9 | F | 19 | 18.998 403 20(7) | 100 | 18.998 403 2(5) | |
| | 10 | Ne | 20 | 19.992 440 1759(20) | 90.48(3) | 20.1797(6) | g,m,r,a | | 21 | 20.993 846 74(4) | 0.27(1) | | 22 | 21.991 385 51(23) | 9.25(3) |
| | 11 | Na | 23 | 22.989 769 67(23) | 100 | 22.989 770(2) | |
| | 12 | Mg | 24 | 23.985 041 90(20) | 78.99(4) | 24.3050(6) | | | 25 | 24.985 837 02(20) | 10.00(1) | | 26 | 25.982 593 04(21) | 11.01(3) |
| | 13 | Al | 27 | 26.981 538 44(14) | 100 | 26.981 538(2) | |
| | 14 | Si | 28 | 27.976 926 5327(20) | 92.2297(7) | 28.0855(3) | r | | 29 | 28.976 494 72(3) | 4.6832(5) | | 30 | 29.973 770 22(5) | 3.0872(5) |
| | 15 | P | 31 | 30.973 761 51(20) | 100 | 30.973 761(2) | |
| | 16 | S | 32 | 31.972 070 69(12) | 94.93(31) | 32.065(5) | g,r | | 33 | 32.971 458 50(12) | 0.76(2) | | 34 | 33.967 866 83(11) | 4.29(28) | | 36 | 35.967 080 88(25) | 0.02(1) |
| | 17 | Cl | 35 | 34.968 852 71(4) | 75.78(4) | 35.453(2) | m | | 37 | 36.965 902 60(5) | 24.22(4) |
| | 18 | Ar | 36 | 35.967 546 28(27) | 0.3365(30) | 39.948(1) | g,r,a | | 38 | 37.962 732 2(5) | 0.0632(5) | | 40 | 39.962 383 123(3) | 99.6003(30) |
| | 19 | K | 39 | 38.963 706 9(3) | 93.2581(44) | 39.0983(1) | | | 40 | 39.963 998 67(29) | 0.0117(1) | | 41 | 40.961 825 97(28) | 6.7302(44) |
| | 20 | Ca | 40 | 39.962 591 2(3) | 96.941(156) | 40.078(4) | g,r,f | | 42 | 41.958 618 3(4) | 0.647(23) | | 43 | 42.958 766 8(5) | 0.135(10) | | 44 | 43.955 481 1(9) | 2.086(110) | | 46 | 45.953 6928(25) | 0.004(3) | | 48 | 47.952 534(4) | 0.187(21) |
| | 21 | Sc | 45 | 44.955 9102(12) | 100 | 44.955 910(8) | |
| | 22 | Ti | 46 | 45.952 6295(12) | 8.25(3) | 47.867(1) | | | 47 | 46.951 7638(10) | 7.44(2) | | 48 | 47.947 9471(10) | 73.72(3) | | 49 | 48.947 8708(10) | 5.41(2) | | 50 | 49.944 7921(11) | 5.18(2) |
| | 23 | V | 50 | 49.947 1628(14) | 0.250(4) | 50.9415(1) | | | 51 | 50.943 9637(14) | 99.750(4) |
| | 24 | Cr | 50 | 49.946 0496(14) | 4.345(13) | 51.9961(6) | | | 52 | 51.940 5119(15) | 83.789(18) | | 53 | 52.940 6538(15) | 9.501(17) | | 54 | 53.938 8849(15) | 2.365(7) |
| | 25 | Mn | 55 | 54.938 0496(14) | 100 | 54.938 049(9) | |
| | 26 | Fe | 54 | 53.939 6148(14) | 5.845(35) | 55.845(2) | | | 56 | 55.934 9421(15) | 91.754(36) | | 57 | 56.935 3987(15) | 2.119(10) | | 58 | 57.933 2805(15) | 0.282(4) |
| | 27 | Co | 59 | 58.933 2002(15) | 100 | 58.933 200(9) | |
| | 28 | Ni | 58 | 57.935 3479(15) | 68.0769(89) | 58.6934(2) | | | 60 | 59.930 7906(15) | 26.2231(77) | | 61 | 60.931 0604(15) | 1.1399(6) | | 62 | 61.928 3488(15) | 3.6345(17) | | 64 | 63.927 9696(16) | 0.9256(9) |
| | 29 | Cu | 63 | 62.929 6011(15) | 69.17(3) | 63.546(3) | r | | 65 | 64.927 7937(19) | 30.83(3) |
| | 30 | Zn | 64 | 63.929 1466(18) | 48.63(60) | 65.409(4) | | | 66 | 65.926 0368(16) | 27.90(27) | | 67 | 66.927 1309(17) | 4.10(13) | | 68 | 67.924 8476(17) | 18.75(51) | | 70 | 69.925 325(4) | 0.62(3) |
| | 31 | Ga | 69 | 68.925 581(3) | 60.108(9) | 69.723(1) | m | | 71 | 70.924 7050(19) | 39.892(9) |
| | 32 | Ge | 70 | 69.924 2504(19) | 20.84(87) | 72.64(1) | h | | 72 | 71.922 0762(16) | 27.54(34) | | 73 | 72.923 4594(16) | 7.73(5) | | 74 | 73.921 1782(16) | 36.28(73) | | 76 | 75.921 4027(16) | 7.61(38) |
| | 33 | As | 75 | 74.921 5964(18) | 100 | 74.921 60(2) | |
| | 34 | Se | 74 | 73.922 4766(16) | 0.89(4) | 78.96(3) | r | | 76 | 75.919 2141(16) | 9.37(29) | | 77 | 76.919 9146(16) | 7.63(16) | | 78 | 77.917 3095(16) | 23.77(28) | | 80 | 79.916 5218(20) | 49.61(41) | | 82 | 81.916 7000(22) | 8.73(22) |
| | 35 | Br | 79 | 78.918 3376(20) | 50.69(7) | 79.904(1) | | | 81 | 80.916 291(3) | 49.31(7) |
| | 36 | Kr | 78 | 77.920 386(7) | 0.35(1) | 83.798(2) | g,m,a | | 80 | 79.916 378(4) | 2.28(6) | | 82 | 81.913 4846(28) | 11.58(14) | | 83 | 82.914 136(3) | 11.49(6) | | 84 | 83.911 507(3) | 57.00(4) | | 86 | 85.910 6103(12) | 17.30(22) |
| | 37 | Rb | 85 | 84.911 7893(25) | 72.17(2) | 85.4678(3) | g | | 87 | 86.909 1835(27) | 27.83(2) |
| | 38 | Sr | 84 | 83.913 425(4) | 0.56(1) | 87.62(1) | g,r,f | | 86 | 85.909 2624(24) | 9.86(1) | | 87 | 86.908 8793(24) | 7.00(1) | | 88 | 87.905 6143(24) | 82.58(1) |
| | 39 | Y | 89 | 88.905 8479(25) | 100 | 88.905 85(2) | |
| | 40 | Zr | 90 | 89.904 7037(23) | 51.45(40) | 91.224(2) | g | | 91 | 90.905 6450(23) | 11.22(5) | | 92 | 91.905 0401(23) | 17.15(8) | | 94 | 93.906 3158(25) | 17.38(28) | | 96 | 95.908 276(3) | 2.80(9) |
| | 41 | Nb | 93 | 92.906 3775(24) | 100 | 92.906 38(2) | |
| | 42 | Mo | 92 | 91.906 810(4) | 14.84(35) | 95.94(2) | g | | 94 | 93.905 0876(20) | 9.25(12) | | 95 | 94.905 8415(20) | 15.92(13) | | 96 | 95.904 6789(20) | 16.68(2) | | 97 | 96.906 0210(20) | 9.55(8) | | 98 | 97.905 4078(20) | 24.13(31) | | 100 | 99.907 477(6) | 9.63(23) |
| | 43 | Tc | 97 | 96.906 365(5) | | [98] | | | 98 | 97.907 216(4) | | | 99 | 98.906 2546(21) | |
| | 44 | Ru | 96 | 95.907 598(8) | 5.54(14) | 101.07(2) | g | | 98 | 97.905 287(7) | 1.87(3) | | 99 | 98.905 9393(21) | 12.76(14) | | 100 | 99.904 2197(22) | 12.60(7) | | 101 | 100.905 5822(22) | 17.06(2) | | 102 | 101.904 3495(22) | 31.55(14) | | 104 | 103.905 430(4) | 18.62(27) |
| | 45 | Rh | 103 | 102.905 504(3) | 100 | 102.905 50(2) | |
| | 46 | Pd | 102 | 101.905 608(3) | 1.02(1) | 106.42(1) | g,r | | 104 | 103.904 035(5) | 11.14(8) | | 105 | 104.905 084(5) | 22.33(8) | | 106 | 105.903 483(5) | 27.33(3) | | 108 | 107.903 894(4) | 26.46(9) | | 110 | 109.905 152(12) | 11.72(9) |
| | 47 | Ag | 107 | 106.905 093(6) | 51.839(8) | 107.8682(2) | g | | 109 | 108.904 756(3) | 48.161(8) |
| | 48 | Cd | 106 | 105.906 458(6) | 1.25(6) | 112.411(8) | g | | 108 | 107.904 183(6) | 0.89(3) | | 110 | 109.903 006(3) | 12.49(18) | | 111 | 110.904 182(3) | 12.80(12) | | 112 | 111.902 7572(30) | 24.13(21) | | 113 | 112.904 4009(30) | 12.22(12) | | 114 | 113.903 3581(30) | 28.73(42) | | 116 | 115.904 755(3) | 7.49(18) |
| | 49 | In | 113 | 112.904 061(4) | 4.29(5) | 114.818(3) | | | 115 | 114.903 878(5) | 95.71(5) |
| | 50 | Sn | 112 | 111.904 821(5) | 0.97(1) | 118.710(7) | g | | 114 | 113.902 782(3) | 0.66(1) | | 115 | 114.903 346(3) | 0.34(1) | | 116 | 115.901 744(3) | 14.54(9) | | 117 | 116.902 954(3) | 7.68(7) | | 118 | 117.901 606(3) | 24.22(9) | | 119 | 118.903 309(3) | 8.59(4) | | 120 | 119.902 1966(27) | 32.58(9) | | 122 | 121.903 4401(29) | 4.63(3) | | 124 | 123.905 2746(15) | 5.79(5) |
| | 51 | Sb | 121 | 120.903 8180(24) | 57.21(5) | 121.760(1) | g | | 123 | 122.904 2157(22) | 42.79(5) |
| | 52 | Te | 120 | 119.904 020(11) | 0.09(1) | 127.60(3) | g,h | | 122 | 121.903 0471(20) | 2.55(12) | | 123 | 122.904 2730(19) | 0.89(3) | | 124 | 123.902 8195(16) | 4.74(14) | | 125 | 124.904 4247(20) | 7.07(15) | | 126 | 125.903 3055(20) | 18.84(25) | | 128 | 127.904 4614(19) | 31.74(8) | | 130 | 129.906 2228(21) | 34.08(62) |
| | 53 | I | 127 | 126.904 468(4) | 100 | 126.904 47(3) | |
| | 54 | Xe | 124 | 123.905 8958(21) | 0.09(1) | 131.293(6) | g,m | | 126 | 125.904 269(7) | 0.09(1) | | 128 | 127.903 5304(15) | 1.92(3) | | 129 | 128.904 779 5(9) | 26.44(24) | | 130 | 129.903 5079(10) | 4.08(2) | | 131 | 130.905 0819(10) | 21.18(3) | | 132 | 131.904 1545(12) | 26.89(6) | | 134 | 133.905 394 5(9) | 10.44(10) | | 136 | 135.907 220(8) | 8.87(16) |
| | 55 | Cs | 133 | 132.905 447(3) | 100 | 132.905 45(2) | |
| | 56 | Ba | 130 | 129.906 310(7) | 0.106(1) | 137.327(7) | | | 132 | 131.905 056(3) | 0.101(1) | | 134 | 133.904 503(3) | 2.417(18) | | 135 | 134.905 683(3) | 6.592(12) | | 136 | 135.904 570(3) | 7.854(24) | | 137 | 136.905 821(3) | 11.232(24) | | 138 | 137.905 241(3) | 71.698(42) |
| | 57 | La | 138 | 137.907 107(4) | 0.090(1) | 138.9055(2) | g | | 139 | 138.906 348(3) | 99.910(1) |
| | 58 | Ce | 136 | 135.907 140(50) | 0.185(2) | 140.116(1) | g,f | | 138 | 137.905 986(11) | 0.251(2) | | 140 | 139.905 434(3) | 88.450(51) | | 142 | 141.909 240(4) | 11.114(51) |
| | 59 | Pr | 141 | 140.907 648(3) | 100 | 140.907 65(2) | |
| | 60 | Nd | 142 | 141.907 719(3) | 27.2(5) | 144.24(3) | g,f | | 143 | 142.909 810(3) | 12.2(2) | | 144 | 143.910 083(3) | 23.8(3) | | 145 | 144.912 569(3) | 8.3(1) | | 146 | 145.913 112(3) | 17.2(3) | | 148 | 147.916 889(3) | 5.7(1) | | 150 | 149.920 887(4) | 5.6(2) |
| | 61 | Pm | 145 | 144.912 744(4) | | [145] | | | 147 | 146.915 134(3) | |
| | 62 | Sm | 144 | 143.911 995(4) | 3.07(7) | 150.36(3) | g | | 147 | 146.914 893(3) | 14.99(18) | | 148 | 147.914 818(3) | 11.24(10) | | 149 | 148.917 180(3) | 13.82(7) | | 150 | 149.917 271(3) | 7.38(1) | | 152 | 151.919 728(3) | 26.75(16) | | 154 | 153.922 205(3) | 22.75(29) |
| | 63 | Eu | 151 | 150.919 846(3) | 47.81(3) | 151.964(1) | g | | 153 | 152.921 226(3) | 52.19(3) |
| | 64 | Gd | 152 | 151.919 788(3) | 0.20(1) | 157.25(3) | g | | 154 | 153.920 862(3) | 2.18(3) | | 155 | 154.922 619(3) | 14.80(12) | | 156 | 155.922 120(3) | 20.47(9) | | 157 | 156.923 957(3) | 15.65(2) | | 158 | 157.924 101(3) | 24.84(7) | | 160 | 159.927 051(3) | 21.86(19) |
| | 65 | Tb | 159 | 158.925 343(3) | 100 | 158.925 34(2) | |
| | 66 | Dy | 156 | 155.924 278(7) | 0.06(1) | 162.500(1) | g | | 158 | 157.924 405(4) | 0.10(1) | | 160 | 159.925 194(3) | 2.34(8) | | 161 | 160.926 930(3) | 18.91(24) | | 162 | 161.926 795(3) | 25.51(26) | | 163 | 162.928 728(3) | 24.90(16) | | 164 | 163.929 171(3) | 28.18(37) |
| | 67 | Ho | 165 | 164.930 319(3) | 100 | 164.930 32(2) | |
| | 68 | Er | 162 | 161.928 775(4) | 0.14(1) | 167.259(3) | g | | 164 | 163.929 197(4) | 1.61(3) | | 166 | 165.930 290(3) | 33.61(35) | | 167 | 166.932 045(3) | 22.93(17) | | 168 | 167.932 368(3) | 26.78(26) | | 170 | 169.935 460(3) | 14.93(27) |
| | 69 | Tm | 169 | 168.934 211(3) | 100 | 168.934 21(2) | |
| | 70 | Yb | 168 | 167.933 894(5) | 0.13(1) | 173.04(3) | g | | 170 | 169.934 759(3) | 3.04(15) | | 171 | 170.936 322(3) | 14.28(57) | | 172 | 171.936 3777(30) | 21.83(67) | | 173 | 172.938 2068(30) | 16.13(27) | | 174 | 173.938 8581(30) | 31.83(92) | | 176 | 175.942 568(3) | 12.76(41) |
| | 71 | Lu | 175 | 174.940 7679(28) | 97.41(2) | 174.967(1) | g | | 176 | 175.942 6824(28) | 2.59(2) |
| | 72 | Hf | 174 | 173.940 040(3) | 0.16(1) | 178.49(2) | f | | 176 | 175.941 4018(29) | 5.26(7) | | 177 | 176.943 2200(27) | 18.60(9) | | 178 | 177.943 6977(27) | 27.28(7) | | 179 | 178.945 8151(27) | 13.62(2) | | 180 | 179.946 5488(27) | 35.08(16) |
| | 73 | Ta | 180 | 179.947 466(3) | 0.012(2) | 180.9479(1) | | | 181 | 180.947 996(3) | 99.988(2) |
| | 74 | W | 180 | 179.946 706(5) | 0.12(1) | 183.84(1) | | | 182 | 181.948 206(3) | 26.50(16) | | 183 | 182.950 2245(29) | 14.31(4) | | 184 | 183.950 9326(29) | 30.64(2) | | 186 | 185.954 362(3) | 28.43(19) |
| | 75 | Re | 185 | 184.952 9557(30) | 37.40(2) | 186.207(1) | | | 187 | 186.955 7508(30) | 62.60(2) |
| | 76 | Os | 184 | 183.952 491(3) | 0.02(1) | 190.23(3) | g,r,f | | 186 | 185.953 838(3) | 1.59(3) | | 187 | 186.955 7479(30) | 1.96(2) | | 188 | 187.955 8360(30) | 13.24(8) | | 189 | 188.958 1449(30) | 16.15(5) | | 190 | 189.958 445(3) | 26.26(2) | | 192 | 191.961 479(4) | 40.78(19) |
| | 77 | Ir | 191 | 190.960 591(3) | 37.3(2) | 192.217(3) | | | 193 | 192.962 924(3) | 62.7(2) |
| | 78 | Pt | 190 | 189.959 930(7) | 0.014(1) | 195.078(2) | | | 192 | 191.961 035(4) | 0.782(7) | | 194 | 193.962 664(3) | 32.967(99) | | 195 | 194.964 774(3) | 33.832(10) | | 196 | 195.964 935(3) | 25.242(41) | | 198 | 197.967 876(4) | 7.163(55) |
| | 79 | Au | 197 | 196.966 552(3) | 100 | 196.966 55(2) | |
| | 80 | Hg | 196 | 195.965 815(4) | 0.15(1) | 200.59(2) | | | 198 | 197.966 752(3) | 9.97(20) | | 199 | 198.968 262(3) | 16.87(22) | | 200 | 199.968 309(3) | 23.10(19) | | 201 | 200.970 285(3) | 13.18(9) | | 202 | 201.970 626(3) | 29.86(26) | | 204 | 203.973 476(3) | 6.87(15) |
| | 81 | Tl | 203 | 202.972 329(3) | 29.524(14) | 204.3833(2) | | | 205 | 204.974 412(3) | 70.476(14) |
| | 82 | Pb | 204 | 203.973 029(3) | 1.4(1) | 207.2(1) | g,r,f | | 206 | 205.974 449(3) | 24.1(1) | | 207 | 206.975 881(3) | 22.1(1) | | 208 | 207.976 636(3) | 52.4(1) |
| | 83 | Bi | 209 | 208.980 383(3) | 100 | 208.980 38(2) | |
| | 84 | Po | 209 | 208.982 416(3) | | [209] | | | 210 | 209.982 857(3) | |
| | 85 | At | 210 | 209.987 131(9) | | [210] | | | 211 | 210.987 481(4) | |
| | 86 | Rn | 211 | 210.990 585(8) | | [222] | | | 220 | 220.011 3841(29) | | | 222 | 222.017 5705(27) | |
| | 87 | Fr | 223 | 223.019 7307(29) | | [223] | |
| | 88 | Ra | 223 | 223.018 497(3) | | [226] | | | 224 | 224.020 2020(29) | | | 226 | 226.025 4026(27) | | | 228 | 228.031 0641(27) | |
| | 89 | Ac | 227 | 227.027 7470(29) | | [227] | |
| | 90 | Th | 230 | 230.033 1266(22) | | | 232 | 232.038 0504(22) | 100 | 232.0381(1) | g |
| | 91 | Pa | 231 | 231.035 8789(28) | 100 | 231.035 88(2) | |
| | 92 | U | 233 | 233.039 628(3) | | | 234 | 234.040 9456(21) | 0.0055(2) | 238.028 91(3) | g,m,r,d,f | | 235 | 235.043 9231(21) | 0.7200(51) | | 236 | 236.045 5619(21) | | | 238 | 238.050 7826(21) | 99.2745(106) |
| | 93 | Np | 237 | 237.048 1673(21) | | [237] | | | 239 | 239.052 9314(23) | |
| | 94 | Pu | 238 | 238.049 5534(21) | | [244] | | | 239 | 239.052 1565(21) | | | 240 | 240.053 8075(21) | | | 241 | 241.056 8453(21) | | | 242 | 242.058 7368(21) | | | 244 | 244.064 198(5) | |
| | 95 | Am | 241 | 241.056 8229(21) | | [243] | | | 243 | 243.061 3727(23) | |
| | 96 | Cm | 243 | 243.061 3822(24) | | [247] | | | 244 | 244.062 7463(21) | | | 245 | 245.065 4856(29) | | | 246 | 246.067 2176(24) | | | 247 | 247.070 347(5) | | | 248 | 248.072 342(5) | |
| | 97 | Bk | 247 | 247.070 299(6) | | [247] | | | 249 | 249.074 980(3) | |
| | 98 | Cf | 249 | 249.074 847(3) | | [251] | | | 250 | 250.076 4000(24) | | | 251 | 251.079 580(5) | | | 252 | 252.081 620(5) | |
| | 99 | Es | 252 | 252.082 970(50) | | [252] | |
| | 100 | Fm | 257 | 257.095 099(7) | | [257] | |
| | 101 | Md | 256 | 256.094 050(60) | | [258] | | | 258 | 258.098 425(5) | |
| | 102 | No | 259 | 259.101 02(11)# | | [259] | |
| | 103 | Lr | 262 | 262.109 69(32)# | | [262] | |
| | 104 | Rf | 261 | 261.108 75(11)# | | [261] | |
| | 105 | Db | 262 | 262.114 15(20)# | | [262] | |
| | 106 | Sg | 266 | 266.121 93(31)# | | [266] | |
| | 107 | Bh | 264 | 264.124 73(30)# | | [264] | |
| | 108 | Hs | 277 | 269.134 11(46)# | | [277] | |
| | 109 | Mt | 268 | 268.138 82(34)# | | [268] | |
| | 110 | Uun | 281 | 271.146 08(20)# | | [281] | |
| | 111 | Uuu | 272 | 272.153 48(36)# | | [272] | |
| | 112 | Uub | 285 | | | [285] | |
| | | | | |
| | 114 | Uuq | 289 | | | [289] | |
| | | | | |
| | 116 | Uuh | 292 | | | [292] | | |
|
|
Download Atomic Weights