Atomic Weights and Isotopic Compositions for All Elements

Atomic Weights and Isotopic Compositions for All Elements
Description of Quantities and Notes

Atomic Number = 1
Atomic Symbol = H
Mass Number = 1
Relative Atomic Mass = 1.00782503223(9)
Isotopic Composition = 0.999885(70)
Standard Atomic Weight = [1.00784,1.00811]
Notes = m

Atomic Number = 1
Atomic Symbol = D
Mass Number = 2
Relative Atomic Mass = 2.01410177812(12)
Isotopic Composition = 0.000115(70)
Standard Atomic Weight = [1.00784,1.00811]
Notes = m

Atomic Number = 1
Atomic Symbol = T
Mass Number = 3
Relative Atomic Mass = 3.0160492779(24)
Isotopic Composition = 
Standard Atomic Weight = [1.00784,1.00811]
Notes = m

Atomic Number = 2
Atomic Symbol = He
Mass Number = 3
Relative Atomic Mass = 3.0160293201(25)
Isotopic Composition = 0.00000134(3)
Standard Atomic Weight = 4.002602(2)
Notes = g,r

Atomic Number = 2
Atomic Symbol = He
Mass Number = 4
Relative Atomic Mass = 4.00260325413(6)
Isotopic Composition = 0.99999866(3)
Standard Atomic Weight = 4.002602(2)
Notes = g,r

Atomic Number = 3
Atomic Symbol = Li
Mass Number = 6
Relative Atomic Mass = 6.0151228874(16)
Isotopic Composition = 0.0759(4)
Standard Atomic Weight = [6.938,6.997]
Notes = m

Atomic Number = 3
Atomic Symbol = Li
Mass Number = 7
Relative Atomic Mass = 7.0160034366(45)
Isotopic Composition = 0.9241(4)
Standard Atomic Weight = [6.938,6.997]
Notes = m

Atomic Number = 4
Atomic Symbol = Be
Mass Number = 9
Relative Atomic Mass = 9.012183065(82)
Isotopic Composition = 1
Standard Atomic Weight = 9.0121831(5)
Notes =  

Atomic Number = 5
Atomic Symbol = B
Mass Number = 10
Relative Atomic Mass = 10.01293695(41)
Isotopic Composition = 0.199(7)
Standard Atomic Weight = [10.806,10.821]
Notes = m

Atomic Number = 5
Atomic Symbol = B
Mass Number = 11
Relative Atomic Mass = 11.00930536(45)
Isotopic Composition = 0.801(7)
Standard Atomic Weight = [10.806,10.821]
Notes = m

Atomic Number = 6
Atomic Symbol = C
Mass Number = 12
Relative Atomic Mass = 12.0000000(00)
Isotopic Composition = 0.9893(8)
Standard Atomic Weight = [12.0096,12.0116]
Notes =  

Atomic Number = 6
Atomic Symbol = C
Mass Number = 13
Relative Atomic Mass = 13.00335483507(23)
Isotopic Composition = 0.0107(8)
Standard Atomic Weight = [12.0096,12.0116]
Notes =  

Atomic Number = 6
Atomic Symbol = C
Mass Number = 14
Relative Atomic Mass = 14.0032419884(40)
Isotopic Composition = 
Standard Atomic Weight = [12.0096,12.0116]
Notes =  

Atomic Number = 7
Atomic Symbol = N
Mass Number = 14
Relative Atomic Mass = 14.00307400443(20)
Isotopic Composition = 0.99636(20)
Standard Atomic Weight = [14.00643,14.00728]
Notes =  

Atomic Number = 7
Atomic Symbol = N
Mass Number = 15
Relative Atomic Mass = 15.00010889888(64)
Isotopic Composition = 0.00364(20)
Standard Atomic Weight = [14.00643,14.00728]
Notes =  

Atomic Number = 8
Atomic Symbol = O
Mass Number = 16
Relative Atomic Mass = 15.99491461957(17)
Isotopic Composition = 0.99757(16)
Standard Atomic Weight = [15.99903,15.99977]
Notes =  

Atomic Number = 8
Atomic Symbol = O
Mass Number = 17
Relative Atomic Mass = 16.99913175650(69)
Isotopic Composition = 0.00038(1)
Standard Atomic Weight = [15.99903,15.99977]
Notes =  

Atomic Number = 8
Atomic Symbol = O
Mass Number = 18
Relative Atomic Mass = 17.99915961286(76)
Isotopic Composition = 0.00205(14)
Standard Atomic Weight = [15.99903,15.99977]
Notes =  

Atomic Number = 9
Atomic Symbol = F
Mass Number = 19
Relative Atomic Mass = 18.99840316273(92)
Isotopic Composition = 1
Standard Atomic Weight = 18.998403163(6)
Notes =  

Atomic Number = 10
Atomic Symbol = Ne
Mass Number = 20
Relative Atomic Mass = 19.9924401762(17)
Isotopic Composition = 0.9048(3)
Standard Atomic Weight = 20.1797(6)
Notes = g,m

Atomic Number = 10
Atomic Symbol = Ne
Mass Number = 21
Relative Atomic Mass = 20.993846685(41)
Isotopic Composition = 0.0027(1)
Standard Atomic Weight = 20.1797(6)
Notes = g,m

Atomic Number = 10
Atomic Symbol = Ne
Mass Number = 22
Relative Atomic Mass = 21.991385114(18)
Isotopic Composition = 0.0925(3)
Standard Atomic Weight = 20.1797(6)
Notes = g,m

Atomic Number = 11
Atomic Symbol = Na
Mass Number = 23
Relative Atomic Mass = 22.9897692820(19)
Isotopic Composition = 1
Standard Atomic Weight = 22.98976928(2)
Notes =  

Atomic Number = 12
Atomic Symbol = Mg
Mass Number = 24
Relative Atomic Mass = 23.985041697(14)
Isotopic Composition = 0.7899(4)
Standard Atomic Weight = [24.304,24.307]
Notes =  

Atomic Number = 12
Atomic Symbol = Mg
Mass Number = 25
Relative Atomic Mass = 24.985836976(50)
Isotopic Composition = 0.1000(1)
Standard Atomic Weight = [24.304,24.307]
Notes =  

Atomic Number = 12
Atomic Symbol = Mg
Mass Number = 26
Relative Atomic Mass = 25.982592968(31)
Isotopic Composition = 0.1101(3)
Standard Atomic Weight = [24.304,24.307]
Notes =  

Atomic Number = 13
Atomic Symbol = Al
Mass Number = 27
Relative Atomic Mass = 26.98153853(11)
Isotopic Composition = 1
Standard Atomic Weight = 26.9815385(7)
Notes =  

Atomic Number = 14
Atomic Symbol = Si
Mass Number = 28
Relative Atomic Mass = 27.97692653465(44)
Isotopic Composition = 0.92223(19)
Standard Atomic Weight = [28.084,28.086]
Notes =  

Atomic Number = 14
Atomic Symbol = Si
Mass Number = 29
Relative Atomic Mass = 28.97649466490(52)
Isotopic Composition = 0.04685(8)
Standard Atomic Weight = [28.084,28.086]
Notes =  

Atomic Number = 14
Atomic Symbol = Si
Mass Number = 30
Relative Atomic Mass = 29.973770136(23)
Isotopic Composition = 0.03092(11)
Standard Atomic Weight = [28.084,28.086]
Notes =  

Atomic Number = 15
Atomic Symbol = P
Mass Number = 31
Relative Atomic Mass = 30.97376199842(70)
Isotopic Composition = 1
Standard Atomic Weight = 30.973761998(5)
Notes =  

Atomic Number = 16
Atomic Symbol = S
Mass Number = 32
Relative Atomic Mass = 31.9720711744(14)
Isotopic Composition = 0.9499(26)
Standard Atomic Weight = [32.059,32.076]
Notes =  

Atomic Number = 16
Atomic Symbol = S
Mass Number = 33
Relative Atomic Mass = 32.9714589098(15)
Isotopic Composition = 0.0075(2)
Standard Atomic Weight = [32.059,32.076]
Notes =  

Atomic Number = 16
Atomic Symbol = S
Mass Number = 34
Relative Atomic Mass = 33.967867004(47)
Isotopic Composition = 0.0425(24)
Standard Atomic Weight = [32.059,32.076]
Notes =  

Atomic Number = 16
Atomic Symbol = S
Mass Number = 36
Relative Atomic Mass = 35.96708071(20)
Isotopic Composition = 0.0001(1)
Standard Atomic Weight = [32.059,32.076]
Notes =  

Atomic Number = 17
Atomic Symbol = Cl
Mass Number = 35
Relative Atomic Mass = 34.968852682(37)
Isotopic Composition = 0.7576(10)
Standard Atomic Weight = [35.446,35.457]
Notes = m

Atomic Number = 17
Atomic Symbol = Cl
Mass Number = 37
Relative Atomic Mass = 36.965902602(55)
Isotopic Composition = 0.2424(10)
Standard Atomic Weight = [35.446,35.457]
Notes = m

Atomic Number = 18
Atomic Symbol = Ar
Mass Number = 36
Relative Atomic Mass = 35.967545105(28)
Isotopic Composition = 0.003336(21)
Standard Atomic Weight = 39.948(1)
Notes = g,r

Atomic Number = 18
Atomic Symbol = Ar
Mass Number = 38
Relative Atomic Mass = 37.96273211(21)
Isotopic Composition = 0.000629(7)
Standard Atomic Weight = 39.948(1)
Notes = g,r

Atomic Number = 18
Atomic Symbol = Ar
Mass Number = 40
Relative Atomic Mass = 39.9623831237(24)
Isotopic Composition = 0.996035(25)
Standard Atomic Weight = 39.948(1)
Notes = g,r

Atomic Number = 19
Atomic Symbol = K
Mass Number = 39
Relative Atomic Mass = 38.9637064864(49)
Isotopic Composition = 0.932581(44)
Standard Atomic Weight = 39.0983(1)
Notes =  

Atomic Number = 19
Atomic Symbol = K
Mass Number = 40
Relative Atomic Mass = 39.963998166(60)
Isotopic Composition = 0.000117(1)
Standard Atomic Weight = 39.0983(1)
Notes =  

Atomic Number = 19
Atomic Symbol = K
Mass Number = 41
Relative Atomic Mass = 40.9618252579(41)
Isotopic Composition = 0.067302(44)
Standard Atomic Weight = 39.0983(1)
Notes =  

Atomic Number = 20
Atomic Symbol = Ca
Mass Number = 40
Relative Atomic Mass = 39.962590863(22)
Isotopic Composition = 0.96941(156)
Standard Atomic Weight = 40.078(4)
Notes = g

Atomic Number = 20
Atomic Symbol = Ca
Mass Number = 42
Relative Atomic Mass = 41.95861783(16)
Isotopic Composition = 0.00647(23)
Standard Atomic Weight = 40.078(4)
Notes = g

Atomic Number = 20
Atomic Symbol = Ca
Mass Number = 43
Relative Atomic Mass = 42.95876644(24)
Isotopic Composition = 0.00135(10)
Standard Atomic Weight = 40.078(4)
Notes = g

Atomic Number = 20
Atomic Symbol = Ca
Mass Number = 44
Relative Atomic Mass = 43.95548156(35)
Isotopic Composition = 0.02086(110)
Standard Atomic Weight = 40.078(4)
Notes = g

Atomic Number = 20
Atomic Symbol = Ca
Mass Number = 46
Relative Atomic Mass = 45.9536890(24)
Isotopic Composition = 0.00004(3)
Standard Atomic Weight = 40.078(4)
Notes = g

Atomic Number = 20
Atomic Symbol = Ca
Mass Number = 48
Relative Atomic Mass = 47.95252276(13)
Isotopic Composition = 0.00187(21)
Standard Atomic Weight = 40.078(4)
Notes = g

Atomic Number = 21
Atomic Symbol = Sc
Mass Number = 45
Relative Atomic Mass = 44.95590828(77)
Isotopic Composition = 1
Standard Atomic Weight = 44.955908(5)
Notes =  

Atomic Number = 22
Atomic Symbol = Ti
Mass Number = 46
Relative Atomic Mass = 45.95262772(35)
Isotopic Composition = 0.0825(3)
Standard Atomic Weight = 47.867(1)
Notes =  

Atomic Number = 22
Atomic Symbol = Ti
Mass Number = 47
Relative Atomic Mass = 46.95175879(38)
Isotopic Composition = 0.0744(2)
Standard Atomic Weight = 47.867(1)
Notes =  

Atomic Number = 22
Atomic Symbol = Ti
Mass Number = 48
Relative Atomic Mass = 47.94794198(38)
Isotopic Composition = 0.7372(3)
Standard Atomic Weight = 47.867(1)
Notes =  

Atomic Number = 22
Atomic Symbol = Ti
Mass Number = 49
Relative Atomic Mass = 48.94786568(39)
Isotopic Composition = 0.0541(2)
Standard Atomic Weight = 47.867(1)
Notes =  

Atomic Number = 22
Atomic Symbol = Ti
Mass Number = 50
Relative Atomic Mass = 49.94478689(39)
Isotopic Composition = 0.0518(2)
Standard Atomic Weight = 47.867(1)
Notes =  

Atomic Number = 23
Atomic Symbol = V
Mass Number = 50
Relative Atomic Mass = 49.94715601(95)
Isotopic Composition = 0.00250(4)
Standard Atomic Weight = 50.9415(1)
Notes =  

Atomic Number = 23
Atomic Symbol = V
Mass Number = 51
Relative Atomic Mass = 50.94395704(94)
Isotopic Composition = 0.99750(4)
Standard Atomic Weight = 50.9415(1)
Notes =  

Atomic Number = 24
Atomic Symbol = Cr
Mass Number = 50
Relative Atomic Mass = 49.94604183(94)
Isotopic Composition = 0.04345(13)
Standard Atomic Weight = 51.9961(6)
Notes =  

Atomic Number = 24
Atomic Symbol = Cr
Mass Number = 52
Relative Atomic Mass = 51.94050623(63)
Isotopic Composition = 0.83789(18)
Standard Atomic Weight = 51.9961(6)
Notes =  

Atomic Number = 24
Atomic Symbol = Cr
Mass Number = 53
Relative Atomic Mass = 52.94064815(62)
Isotopic Composition = 0.09501(17)
Standard Atomic Weight = 51.9961(6)
Notes =  

Atomic Number = 24
Atomic Symbol = Cr
Mass Number = 54
Relative Atomic Mass = 53.93887916(61)
Isotopic Composition = 0.02365(7)
Standard Atomic Weight = 51.9961(6)
Notes =  

Atomic Number = 25
Atomic Symbol = Mn
Mass Number = 55
Relative Atomic Mass = 54.93804391(48)
Isotopic Composition = 1
Standard Atomic Weight = 54.938044(3)
Notes =  

Atomic Number = 26
Atomic Symbol = Fe
Mass Number = 54
Relative Atomic Mass = 53.93960899(53)
Isotopic Composition = 0.05845(35)
Standard Atomic Weight = 55.845(2)
Notes =  

Atomic Number = 26
Atomic Symbol = Fe
Mass Number = 56
Relative Atomic Mass = 55.93493633(49)
Isotopic Composition = 0.91754(36)
Standard Atomic Weight = 55.845(2)
Notes =  

Atomic Number = 26
Atomic Symbol = Fe
Mass Number = 57
Relative Atomic Mass = 56.93539284(49)
Isotopic Composition = 0.02119(10)
Standard Atomic Weight = 55.845(2)
Notes =  

Atomic Number = 26
Atomic Symbol = Fe
Mass Number = 58
Relative Atomic Mass = 57.93327443(53)
Isotopic Composition = 0.00282(4)
Standard Atomic Weight = 55.845(2)
Notes =  

Atomic Number = 27
Atomic Symbol = Co
Mass Number = 59
Relative Atomic Mass = 58.93319429(56)
Isotopic Composition = 1
Standard Atomic Weight = 58.933194(4)
Notes =  

Atomic Number = 28
Atomic Symbol = Ni
Mass Number = 58
Relative Atomic Mass = 57.93534241(52)
Isotopic Composition = 0.68077(19)
Standard Atomic Weight = 58.6934(4)
Notes = r

Atomic Number = 28
Atomic Symbol = Ni
Mass Number = 60
Relative Atomic Mass = 59.93078588(52)
Isotopic Composition = 0.26223(15)
Standard Atomic Weight = 58.6934(4)
Notes = r

Atomic Number = 28
Atomic Symbol = Ni
Mass Number = 61
Relative Atomic Mass = 60.93105557(52)
Isotopic Composition = 0.011399(13)
Standard Atomic Weight = 58.6934(4)
Notes = r

Atomic Number = 28
Atomic Symbol = Ni
Mass Number = 62
Relative Atomic Mass = 61.92834537(55)
Isotopic Composition = 0.036346(40)
Standard Atomic Weight = 58.6934(4)
Notes = r

Atomic Number = 28
Atomic Symbol = Ni
Mass Number = 64
Relative Atomic Mass = 63.92796682(58)
Isotopic Composition = 0.009255(19)
Standard Atomic Weight = 58.6934(4)
Notes = r

Atomic Number = 29
Atomic Symbol = Cu
Mass Number = 63
Relative Atomic Mass = 62.92959772(56)
Isotopic Composition = 0.6915(15)
Standard Atomic Weight = 63.546(3)
Notes = r

Atomic Number = 29
Atomic Symbol = Cu
Mass Number = 65
Relative Atomic Mass = 64.92778970(71)
Isotopic Composition = 0.3085(15)
Standard Atomic Weight = 63.546(3)
Notes = r

Atomic Number = 30
Atomic Symbol = Zn
Mass Number = 64
Relative Atomic Mass = 63.92914201(71)
Isotopic Composition = 0.4917(75)
Standard Atomic Weight = 65.38(2)
Notes = r

Atomic Number = 30
Atomic Symbol = Zn
Mass Number = 66
Relative Atomic Mass = 65.92603381(94)
Isotopic Composition = 0.2773(98)
Standard Atomic Weight = 65.38(2)
Notes = r

Atomic Number = 30
Atomic Symbol = Zn
Mass Number = 67
Relative Atomic Mass = 66.92712775(96)
Isotopic Composition = 0.0404(16)
Standard Atomic Weight = 65.38(2)
Notes = r

Atomic Number = 30
Atomic Symbol = Zn
Mass Number = 68
Relative Atomic Mass = 67.92484455(98)
Isotopic Composition = 0.1845(63)
Standard Atomic Weight = 65.38(2)
Notes = r

Atomic Number = 30
Atomic Symbol = Zn
Mass Number = 70
Relative Atomic Mass = 69.9253192(21)
Isotopic Composition = 0.0061(10)
Standard Atomic Weight = 65.38(2)
Notes = r

Atomic Number = 31
Atomic Symbol = Ga
Mass Number = 69
Relative Atomic Mass = 68.9255735(13)
Isotopic Composition = 0.60108(9)
Standard Atomic Weight = 69.723(1)
Notes =  

Atomic Number = 31
Atomic Symbol = Ga
Mass Number = 71
Relative Atomic Mass = 70.92470258(87)
Isotopic Composition = 0.39892(9)
Standard Atomic Weight = 69.723(1)
Notes =  

Atomic Number = 32
Atomic Symbol = Ge
Mass Number = 70
Relative Atomic Mass = 69.92424875(90)
Isotopic Composition = 0.2057(27)
Standard Atomic Weight = 72.630(8)
Notes =  

Atomic Number = 32
Atomic Symbol = Ge
Mass Number = 72
Relative Atomic Mass = 71.922075826(81)
Isotopic Composition = 0.2745(32)
Standard Atomic Weight = 72.630(8)
Notes =  

Atomic Number = 32
Atomic Symbol = Ge
Mass Number = 73
Relative Atomic Mass = 72.923458956(61)
Isotopic Composition = 0.0775(12)
Standard Atomic Weight = 72.630(8)
Notes =  

Atomic Number = 32
Atomic Symbol = Ge
Mass Number = 74
Relative Atomic Mass = 73.921177761(13)
Isotopic Composition = 0.3650(20)
Standard Atomic Weight = 72.630(8)
Notes =  

Atomic Number = 32
Atomic Symbol = Ge
Mass Number = 76
Relative Atomic Mass = 75.921402726(19)
Isotopic Composition = 0.0773(12)
Standard Atomic Weight = 72.630(8)
Notes =  

Atomic Number = 33
Atomic Symbol = As
Mass Number = 75
Relative Atomic Mass = 74.92159457(95)
Isotopic Composition = 1
Standard Atomic Weight = 74.921595(6)
Notes =  

Atomic Number = 34
Atomic Symbol = Se
Mass Number = 74
Relative Atomic Mass = 73.922475934(15)
Isotopic Composition = 0.0089(4)
Standard Atomic Weight = 78.971(8)
Notes = r

Atomic Number = 34
Atomic Symbol = Se
Mass Number = 76
Relative Atomic Mass = 75.919213704(17)
Isotopic Composition = 0.0937(29)
Standard Atomic Weight = 78.971(8)
Notes = r

Atomic Number = 34
Atomic Symbol = Se
Mass Number = 77
Relative Atomic Mass = 76.919914154(67)
Isotopic Composition = 0.0763(16)
Standard Atomic Weight = 78.971(8)
Notes = r

Atomic Number = 34
Atomic Symbol = Se
Mass Number = 78
Relative Atomic Mass = 77.91730928(20)
Isotopic Composition = 0.2377(28)
Standard Atomic Weight = 78.971(8)
Notes = r

Atomic Number = 34
Atomic Symbol = Se
Mass Number = 80
Relative Atomic Mass = 79.9165218(13)
Isotopic Composition = 0.4961(41)
Standard Atomic Weight = 78.971(8)
Notes = r

Atomic Number = 34
Atomic Symbol = Se
Mass Number = 82
Relative Atomic Mass = 81.9166995(15)
Isotopic Composition = 0.0873(22)
Standard Atomic Weight = 78.971(8)
Notes = r

Atomic Number = 35
Atomic Symbol = Br
Mass Number = 79
Relative Atomic Mass = 78.9183376(14)
Isotopic Composition = 0.5069(7)
Standard Atomic Weight = [79.901,79.907]
Notes =  

Atomic Number = 35
Atomic Symbol = Br
Mass Number = 81
Relative Atomic Mass = 80.9162897(14)
Isotopic Composition = 0.4931(7)
Standard Atomic Weight = [79.901,79.907]
Notes =  

Atomic Number = 36
Atomic Symbol = Kr
Mass Number = 78
Relative Atomic Mass = 77.92036494(76)
Isotopic Composition = 0.00355(3)
Standard Atomic Weight = 83.798(2)
Notes = g,m

Atomic Number = 36
Atomic Symbol = Kr
Mass Number = 80
Relative Atomic Mass = 79.91637808(75)
Isotopic Composition = 0.02286(10)
Standard Atomic Weight = 83.798(2)
Notes = g,m

Atomic Number = 36
Atomic Symbol = Kr
Mass Number = 82
Relative Atomic Mass = 81.91348273(94)
Isotopic Composition = 0.11593(31)
Standard Atomic Weight = 83.798(2)
Notes = g,m

Atomic Number = 36
Atomic Symbol = Kr
Mass Number = 83
Relative Atomic Mass = 82.91412716(32)
Isotopic Composition = 0.11500(19)
Standard Atomic Weight = 83.798(2)
Notes = g,m

Atomic Number = 36
Atomic Symbol = Kr
Mass Number = 84
Relative Atomic Mass = 83.9114977282(44)
Isotopic Composition = 0.56987(15)
Standard Atomic Weight = 83.798(2)
Notes = g,m

Atomic Number = 36
Atomic Symbol = Kr
Mass Number = 86
Relative Atomic Mass = 85.9106106269(41)
Isotopic Composition = 0.17279(41)
Standard Atomic Weight = 83.798(2)
Notes = g,m

Atomic Number = 37
Atomic Symbol = Rb
Mass Number = 85
Relative Atomic Mass = 84.9117897379(54)
Isotopic Composition = 0.7217(2)
Standard Atomic Weight = 85.4678(3)
Notes = g

Atomic Number = 37
Atomic Symbol = Rb
Mass Number = 87
Relative Atomic Mass = 86.9091805310(60)
Isotopic Composition = 0.2783(2)
Standard Atomic Weight = 85.4678(3)
Notes = g

Atomic Number = 38
Atomic Symbol = Sr
Mass Number = 84
Relative Atomic Mass = 83.9134191(13)
Isotopic Composition = 0.0056(1)
Standard Atomic Weight = 87.62(1)
Notes = g,r

Atomic Number = 38
Atomic Symbol = Sr
Mass Number = 86
Relative Atomic Mass = 85.9092606(12)
Isotopic Composition = 0.0986(1)
Standard Atomic Weight = 87.62(1)
Notes = g,r

Atomic Number = 38
Atomic Symbol = Sr
Mass Number = 87
Relative Atomic Mass = 86.9088775(12)
Isotopic Composition = 0.0700(1)
Standard Atomic Weight = 87.62(1)
Notes = g,r

Atomic Number = 38
Atomic Symbol = Sr
Mass Number = 88
Relative Atomic Mass = 87.9056125(12)
Isotopic Composition = 0.8258(1)
Standard Atomic Weight = 87.62(1)
Notes = g,r

Atomic Number = 39
Atomic Symbol = Y
Mass Number = 89
Relative Atomic Mass = 88.9058403(24)
Isotopic Composition = 1
Standard Atomic Weight = 88.90584(2)
Notes =  

Atomic Number = 40
Atomic Symbol = Zr
Mass Number = 90
Relative Atomic Mass = 89.9046977(20)
Isotopic Composition = 0.5145(40)
Standard Atomic Weight = 91.224(2)
Notes = g

Atomic Number = 40
Atomic Symbol = Zr
Mass Number = 91
Relative Atomic Mass = 90.9056396(20)
Isotopic Composition = 0.1122(5)
Standard Atomic Weight = 91.224(2)
Notes = g

Atomic Number = 40
Atomic Symbol = Zr
Mass Number = 92
Relative Atomic Mass = 91.9050347(20)
Isotopic Composition = 0.1715(8)
Standard Atomic Weight = 91.224(2)
Notes = g

Atomic Number = 40
Atomic Symbol = Zr
Mass Number = 94
Relative Atomic Mass = 93.9063108(20)
Isotopic Composition = 0.1738(28)
Standard Atomic Weight = 91.224(2)
Notes = g

Atomic Number = 40
Atomic Symbol = Zr
Mass Number = 96
Relative Atomic Mass = 95.9082714(21)
Isotopic Composition = 0.0280(9)
Standard Atomic Weight = 91.224(2)
Notes = g

Atomic Number = 41
Atomic Symbol = Nb
Mass Number = 93
Relative Atomic Mass = 92.9063730(20)
Isotopic Composition = 1
Standard Atomic Weight = 92.90637(2)
Notes =  

Atomic Number = 42
Atomic Symbol = Mo
Mass Number = 92
Relative Atomic Mass = 91.90680796(84)
Isotopic Composition = 0.1453(30)
Standard Atomic Weight = 95.95(1)
Notes = g

Atomic Number = 42
Atomic Symbol = Mo
Mass Number = 94
Relative Atomic Mass = 93.90508490(48)
Isotopic Composition = 0.0915(9)
Standard Atomic Weight = 95.95(1)
Notes = g

Atomic Number = 42
Atomic Symbol = Mo
Mass Number = 95
Relative Atomic Mass = 94.90583877(47)
Isotopic Composition = 0.1584(11)
Standard Atomic Weight = 95.95(1)
Notes = g

Atomic Number = 42
Atomic Symbol = Mo
Mass Number = 96
Relative Atomic Mass = 95.90467612(47)
Isotopic Composition = 0.1667(15)
Standard Atomic Weight = 95.95(1)
Notes = g

Atomic Number = 42
Atomic Symbol = Mo
Mass Number = 97
Relative Atomic Mass = 96.90601812(49)
Isotopic Composition = 0.0960(14)
Standard Atomic Weight = 95.95(1)
Notes = g

Atomic Number = 42
Atomic Symbol = Mo
Mass Number = 98
Relative Atomic Mass = 97.90540482(49)
Isotopic Composition = 0.2439(37)
Standard Atomic Weight = 95.95(1)
Notes = g

Atomic Number = 42
Atomic Symbol = Mo
Mass Number = 100
Relative Atomic Mass = 99.9074718(11)
Isotopic Composition = 0.0982(31)
Standard Atomic Weight = 95.95(1)
Notes = g

Atomic Number = 43
Atomic Symbol = Tc
Mass Number = 97
Relative Atomic Mass = 96.9063667(40)
Isotopic Composition = 
Standard Atomic Weight = [98]
Notes =  

Atomic Number = 43
Atomic Symbol = Tc
Mass Number = 98
Relative Atomic Mass = 97.9072124(36)
Isotopic Composition = 
Standard Atomic Weight = [98]
Notes =  

Atomic Number = 43
Atomic Symbol = Tc
Mass Number = 99
Relative Atomic Mass = 98.9062508(10)
Isotopic Composition = 
Standard Atomic Weight = [98]
Notes =  

Atomic Number = 44
Atomic Symbol = Ru
Mass Number = 96
Relative Atomic Mass = 95.90759025(49)
Isotopic Composition = 0.0554(14)
Standard Atomic Weight = 101.07(2)
Notes = g

Atomic Number = 44
Atomic Symbol = Ru
Mass Number = 98
Relative Atomic Mass = 97.9052868(69)
Isotopic Composition = 0.0187(3)
Standard Atomic Weight = 101.07(2)
Notes = g

Atomic Number = 44
Atomic Symbol = Ru
Mass Number = 99
Relative Atomic Mass = 98.9059341(11)
Isotopic Composition = 0.1276(14)
Standard Atomic Weight = 101.07(2)
Notes = g

Atomic Number = 44
Atomic Symbol = Ru
Mass Number = 100
Relative Atomic Mass = 99.9042143(11)
Isotopic Composition = 0.1260(7)
Standard Atomic Weight = 101.07(2)
Notes = g

Atomic Number = 44
Atomic Symbol = Ru
Mass Number = 101
Relative Atomic Mass = 100.9055769(12)
Isotopic Composition = 0.1706(2)
Standard Atomic Weight = 101.07(2)
Notes = g

Atomic Number = 44
Atomic Symbol = Ru
Mass Number = 102
Relative Atomic Mass = 101.9043441(12)
Isotopic Composition = 0.3155(14)
Standard Atomic Weight = 101.07(2)
Notes = g

Atomic Number = 44
Atomic Symbol = Ru
Mass Number = 104
Relative Atomic Mass = 103.9054275(28)
Isotopic Composition = 0.1862(27)
Standard Atomic Weight = 101.07(2)
Notes = g

Atomic Number = 45
Atomic Symbol = Rh
Mass Number = 103
Relative Atomic Mass = 102.9054980(26)
Isotopic Composition = 1
Standard Atomic Weight = 102.90550(2)
Notes =  

Atomic Number = 46
Atomic Symbol = Pd
Mass Number = 102
Relative Atomic Mass = 101.9056022(28)
Isotopic Composition = 0.0102(1)
Standard Atomic Weight = 106.42(1)
Notes = g

Atomic Number = 46
Atomic Symbol = Pd
Mass Number = 104
Relative Atomic Mass = 103.9040305(14)
Isotopic Composition = 0.1114(8)
Standard Atomic Weight = 106.42(1)
Notes = g

Atomic Number = 46
Atomic Symbol = Pd
Mass Number = 105
Relative Atomic Mass = 104.9050796(12)
Isotopic Composition = 0.2233(8)
Standard Atomic Weight = 106.42(1)
Notes = g

Atomic Number = 46
Atomic Symbol = Pd
Mass Number = 106
Relative Atomic Mass = 105.9034804(12)
Isotopic Composition = 0.2733(3)
Standard Atomic Weight = 106.42(1)
Notes = g

Atomic Number = 46
Atomic Symbol = Pd
Mass Number = 108
Relative Atomic Mass = 107.9038916(12)
Isotopic Composition = 0.2646(9)
Standard Atomic Weight = 106.42(1)
Notes = g

Atomic Number = 46
Atomic Symbol = Pd
Mass Number = 110
Relative Atomic Mass = 109.90517220(75)
Isotopic Composition = 0.1172(9)
Standard Atomic Weight = 106.42(1)
Notes = g

Atomic Number = 47
Atomic Symbol = Ag
Mass Number = 107
Relative Atomic Mass = 106.9050916(26)
Isotopic Composition = 0.51839(8)
Standard Atomic Weight = 107.8682(2)
Notes = g

Atomic Number = 47
Atomic Symbol = Ag
Mass Number = 109
Relative Atomic Mass = 108.9047553(14)
Isotopic Composition = 0.48161(8)
Standard Atomic Weight = 107.8682(2)
Notes = g

Atomic Number = 48
Atomic Symbol = Cd
Mass Number = 106
Relative Atomic Mass = 105.9064599(12)
Isotopic Composition = 0.0125(6)
Standard Atomic Weight = 112.414(4)
Notes = g

Atomic Number = 48
Atomic Symbol = Cd
Mass Number = 108
Relative Atomic Mass = 107.9041834(12)
Isotopic Composition = 0.0089(3)
Standard Atomic Weight = 112.414(4)
Notes = g

Atomic Number = 48
Atomic Symbol = Cd
Mass Number = 110
Relative Atomic Mass = 109.90300661(61)
Isotopic Composition = 0.1249(18)
Standard Atomic Weight = 112.414(4)
Notes = g

Atomic Number = 48
Atomic Symbol = Cd
Mass Number = 111
Relative Atomic Mass = 110.90418287(61)
Isotopic Composition = 0.1280(12)
Standard Atomic Weight = 112.414(4)
Notes = g

Atomic Number = 48
Atomic Symbol = Cd
Mass Number = 112
Relative Atomic Mass = 111.90276287(60)
Isotopic Composition = 0.2413(21)
Standard Atomic Weight = 112.414(4)
Notes = g

Atomic Number = 48
Atomic Symbol = Cd
Mass Number = 113
Relative Atomic Mass = 112.90440813(45)
Isotopic Composition = 0.1222(12)
Standard Atomic Weight = 112.414(4)
Notes = g

Atomic Number = 48
Atomic Symbol = Cd
Mass Number = 114
Relative Atomic Mass = 113.90336509(43)
Isotopic Composition = 0.2873(42)
Standard Atomic Weight = 112.414(4)
Notes = g

Atomic Number = 48
Atomic Symbol = Cd
Mass Number = 116
Relative Atomic Mass = 115.90476315(17)
Isotopic Composition = 0.0749(18)
Standard Atomic Weight = 112.414(4)
Notes = g

Atomic Number = 49
Atomic Symbol = In
Mass Number = 113
Relative Atomic Mass = 112.90406184(91)
Isotopic Composition = 0.0429(5)
Standard Atomic Weight = 114.818(1)
Notes =  

Atomic Number = 49
Atomic Symbol = In
Mass Number = 115
Relative Atomic Mass = 114.903878776(12)
Isotopic Composition = 0.9571(5)
Standard Atomic Weight = 114.818(1)
Notes =  

Atomic Number = 50
Atomic Symbol = Sn
Mass Number = 112
Relative Atomic Mass = 111.90482387(61)
Isotopic Composition = 0.0097(1)
Standard Atomic Weight = 118.710(7)
Notes = g

Atomic Number = 50
Atomic Symbol = Sn
Mass Number = 114
Relative Atomic Mass = 113.9027827(10)
Isotopic Composition = 0.0066(1)
Standard Atomic Weight = 118.710(7)
Notes = g

Atomic Number = 50
Atomic Symbol = Sn
Mass Number = 115
Relative Atomic Mass = 114.903344699(16)
Isotopic Composition = 0.0034(1)
Standard Atomic Weight = 118.710(7)
Notes = g

Atomic Number = 50
Atomic Symbol = Sn
Mass Number = 116
Relative Atomic Mass = 115.90174280(10)
Isotopic Composition = 0.1454(9)
Standard Atomic Weight = 118.710(7)
Notes = g

Atomic Number = 50
Atomic Symbol = Sn
Mass Number = 117
Relative Atomic Mass = 116.90295398(52)
Isotopic Composition = 0.0768(7)
Standard Atomic Weight = 118.710(7)
Notes = g

Atomic Number = 50
Atomic Symbol = Sn
Mass Number = 118
Relative Atomic Mass = 117.90160657(54)
Isotopic Composition = 0.2422(9)
Standard Atomic Weight = 118.710(7)
Notes = g

Atomic Number = 50
Atomic Symbol = Sn
Mass Number = 119
Relative Atomic Mass = 118.90331117(78)
Isotopic Composition = 0.0859(4)
Standard Atomic Weight = 118.710(7)
Notes = g

Atomic Number = 50
Atomic Symbol = Sn
Mass Number = 120
Relative Atomic Mass = 119.90220163(97)
Isotopic Composition = 0.3258(9)
Standard Atomic Weight = 118.710(7)
Notes = g

Atomic Number = 50
Atomic Symbol = Sn
Mass Number = 122
Relative Atomic Mass = 121.9034438(26)
Isotopic Composition = 0.0463(3)
Standard Atomic Weight = 118.710(7)
Notes = g

Atomic Number = 50
Atomic Symbol = Sn
Mass Number = 124
Relative Atomic Mass = 123.9052766(11)
Isotopic Composition = 0.0579(5)
Standard Atomic Weight = 118.710(7)
Notes = g

Atomic Number = 51
Atomic Symbol = Sb
Mass Number = 121
Relative Atomic Mass = 120.9038120(30)
Isotopic Composition = 0.5721(5)
Standard Atomic Weight = 121.760(1)
Notes = g

Atomic Number = 51
Atomic Symbol = Sb
Mass Number = 123
Relative Atomic Mass = 122.9042132(23)
Isotopic Composition = 0.4279(5)
Standard Atomic Weight = 121.760(1)
Notes = g

Atomic Number = 52
Atomic Symbol = Te
Mass Number = 120
Relative Atomic Mass = 119.9040593(33)
Isotopic Composition = 0.0009(1)
Standard Atomic Weight = 127.60(3)
Notes = g

Atomic Number = 52
Atomic Symbol = Te
Mass Number = 122
Relative Atomic Mass = 121.9030435(16)
Isotopic Composition = 0.0255(12)
Standard Atomic Weight = 127.60(3)
Notes = g

Atomic Number = 52
Atomic Symbol = Te
Mass Number = 123
Relative Atomic Mass = 122.9042698(16)
Isotopic Composition = 0.0089(3)
Standard Atomic Weight = 127.60(3)
Notes = g

Atomic Number = 52
Atomic Symbol = Te
Mass Number = 124
Relative Atomic Mass = 123.9028171(16)
Isotopic Composition = 0.0474(14)
Standard Atomic Weight = 127.60(3)
Notes = g

Atomic Number = 52
Atomic Symbol = Te
Mass Number = 125
Relative Atomic Mass = 124.9044299(16)
Isotopic Composition = 0.0707(15)
Standard Atomic Weight = 127.60(3)
Notes = g

Atomic Number = 52
Atomic Symbol = Te
Mass Number = 126
Relative Atomic Mass = 125.9033109(16)
Isotopic Composition = 0.1884(25)
Standard Atomic Weight = 127.60(3)
Notes = g

Atomic Number = 52
Atomic Symbol = Te
Mass Number = 128
Relative Atomic Mass = 127.90446128(93)
Isotopic Composition = 0.3174(8)
Standard Atomic Weight = 127.60(3)
Notes = g

Atomic Number = 52
Atomic Symbol = Te
Mass Number = 130
Relative Atomic Mass = 129.906222748(12)
Isotopic Composition = 0.3408(62)
Standard Atomic Weight = 127.60(3)
Notes = g

Atomic Number = 53
Atomic Symbol = I
Mass Number = 127
Relative Atomic Mass = 126.9044719(39)
Isotopic Composition = 1
Standard Atomic Weight = 126.90447(3)
Notes =  

Atomic Number = 54
Atomic Symbol = Xe
Mass Number = 124
Relative Atomic Mass = 123.9058920(19)
Isotopic Composition = 0.000952(3)
Standard Atomic Weight = 131.293(6)
Notes = g,m

Atomic Number = 54
Atomic Symbol = Xe
Mass Number = 126
Relative Atomic Mass = 125.9042983(38)
Isotopic Composition = 0.000890(2)
Standard Atomic Weight = 131.293(6)
Notes = g,m

Atomic Number = 54
Atomic Symbol = Xe
Mass Number = 128
Relative Atomic Mass = 127.9035310(11)
Isotopic Composition = 0.019102(8)
Standard Atomic Weight = 131.293(6)
Notes = g,m

Atomic Number = 54
Atomic Symbol = Xe
Mass Number = 129
Relative Atomic Mass = 128.9047808611(60)
Isotopic Composition = 0.264006(82)
Standard Atomic Weight = 131.293(6)
Notes = g,m

Atomic Number = 54
Atomic Symbol = Xe
Mass Number = 130
Relative Atomic Mass = 129.903509349(10)
Isotopic Composition = 0.040710(13)
Standard Atomic Weight = 131.293(6)
Notes = g,m

Atomic Number = 54
Atomic Symbol = Xe
Mass Number = 131
Relative Atomic Mass = 130.90508406(24)
Isotopic Composition = 0.212324(30)
Standard Atomic Weight = 131.293(6)
Notes = g,m

Atomic Number = 54
Atomic Symbol = Xe
Mass Number = 132
Relative Atomic Mass = 131.9041550856(56)
Isotopic Composition = 0.269086(33)
Standard Atomic Weight = 131.293(6)
Notes = g,m

Atomic Number = 54
Atomic Symbol = Xe
Mass Number = 134
Relative Atomic Mass = 133.90539466(90)
Isotopic Composition = 0.104357(21)
Standard Atomic Weight = 131.293(6)
Notes = g,m

Atomic Number = 54
Atomic Symbol = Xe
Mass Number = 136
Relative Atomic Mass = 135.907214484(11)
Isotopic Composition = 0.088573(44)
Standard Atomic Weight = 131.293(6)
Notes = g,m

Atomic Number = 55
Atomic Symbol = Cs
Mass Number = 133
Relative Atomic Mass = 132.9054519610(80)
Isotopic Composition = 1
Standard Atomic Weight = 132.90545196(6)
Notes =  

Atomic Number = 56
Atomic Symbol = Ba
Mass Number = 130
Relative Atomic Mass = 129.9063207(28)
Isotopic Composition = 0.00106(1)
Standard Atomic Weight = 137.327(7)
Notes =  

Atomic Number = 56
Atomic Symbol = Ba
Mass Number = 132
Relative Atomic Mass = 131.9050611(11)
Isotopic Composition = 0.00101(1)
Standard Atomic Weight = 137.327(7)
Notes =  

Atomic Number = 56
Atomic Symbol = Ba
Mass Number = 134
Relative Atomic Mass = 133.90450818(30)
Isotopic Composition = 0.02417(18)
Standard Atomic Weight = 137.327(7)
Notes =  

Atomic Number = 56
Atomic Symbol = Ba
Mass Number = 135
Relative Atomic Mass = 134.90568838(29)
Isotopic Composition = 0.06592(12)
Standard Atomic Weight = 137.327(7)
Notes =  

Atomic Number = 56
Atomic Symbol = Ba
Mass Number = 136
Relative Atomic Mass = 135.90457573(29)
Isotopic Composition = 0.07854(24)
Standard Atomic Weight = 137.327(7)
Notes =  

Atomic Number = 56
Atomic Symbol = Ba
Mass Number = 137
Relative Atomic Mass = 136.90582714(30)
Isotopic Composition = 0.11232(24)
Standard Atomic Weight = 137.327(7)
Notes =  

Atomic Number = 56
Atomic Symbol = Ba
Mass Number = 138
Relative Atomic Mass = 137.90524700(31)
Isotopic Composition = 0.71698(42)
Standard Atomic Weight = 137.327(7)
Notes =  

Atomic Number = 57
Atomic Symbol = La
Mass Number = 138
Relative Atomic Mass = 137.9071149(37)
Isotopic Composition = 0.0008881(71)
Standard Atomic Weight = 138.90547(7)
Notes = g

Atomic Number = 57
Atomic Symbol = La
Mass Number = 139
Relative Atomic Mass = 138.9063563(24)
Isotopic Composition = 0.9991119(71)
Standard Atomic Weight = 138.90547(7)
Notes = g

Atomic Number = 58
Atomic Symbol = Ce
Mass Number = 136
Relative Atomic Mass = 135.90712921(41)
Isotopic Composition = 0.00185(2)
Standard Atomic Weight = 140.116(1)
Notes = g

Atomic Number = 58
Atomic Symbol = Ce
Mass Number = 138
Relative Atomic Mass = 137.905991(11)
Isotopic Composition = 0.00251(2)
Standard Atomic Weight = 140.116(1)
Notes = g

Atomic Number = 58
Atomic Symbol = Ce
Mass Number = 140
Relative Atomic Mass = 139.9054431(23)
Isotopic Composition = 0.88450(51)
Standard Atomic Weight = 140.116(1)
Notes = g

Atomic Number = 58
Atomic Symbol = Ce
Mass Number = 142
Relative Atomic Mass = 141.9092504(29)
Isotopic Composition = 0.11114(51)
Standard Atomic Weight = 140.116(1)
Notes = g

Atomic Number = 59
Atomic Symbol = Pr
Mass Number = 141
Relative Atomic Mass = 140.9076576(23)
Isotopic Composition = 1
Standard Atomic Weight = 140.90766(2)
Notes =  

Atomic Number = 60
Atomic Symbol = Nd
Mass Number = 142
Relative Atomic Mass = 141.9077290(20)
Isotopic Composition = 0.27152(40)
Standard Atomic Weight = 144.242(3)
Notes = g

Atomic Number = 60
Atomic Symbol = Nd
Mass Number = 143
Relative Atomic Mass = 142.9098200(20)
Isotopic Composition = 0.12174(26)
Standard Atomic Weight = 144.242(3)
Notes = g

Atomic Number = 60
Atomic Symbol = Nd
Mass Number = 144
Relative Atomic Mass = 143.9100930(20)
Isotopic Composition = 0.23798(19)
Standard Atomic Weight = 144.242(3)
Notes = g

Atomic Number = 60
Atomic Symbol = Nd
Mass Number = 145
Relative Atomic Mass = 144.9125793(20)
Isotopic Composition = 0.08293(12)
Standard Atomic Weight = 144.242(3)
Notes = g

Atomic Number = 60
Atomic Symbol = Nd
Mass Number = 146
Relative Atomic Mass = 145.9131226(20)
Isotopic Composition = 0.17189(32)
Standard Atomic Weight = 144.242(3)
Notes = g

Atomic Number = 60
Atomic Symbol = Nd
Mass Number = 148
Relative Atomic Mass = 147.9168993(26)
Isotopic Composition = 0.05756(21)
Standard Atomic Weight = 144.242(3)
Notes = g

Atomic Number = 60
Atomic Symbol = Nd
Mass Number = 150
Relative Atomic Mass = 149.9209022(18)
Isotopic Composition = 0.05638(28)
Standard Atomic Weight = 144.242(3)
Notes = g

Atomic Number = 61
Atomic Symbol = Pm
Mass Number = 145
Relative Atomic Mass = 144.9127559(33)
Isotopic Composition = 
Standard Atomic Weight = [145]
Notes =  

Atomic Number = 61
Atomic Symbol = Pm
Mass Number = 147
Relative Atomic Mass = 146.9151450(19)
Isotopic Composition = 
Standard Atomic Weight = [145]
Notes =  

Atomic Number = 62
Atomic Symbol = Sm
Mass Number = 144
Relative Atomic Mass = 143.9120065(21)
Isotopic Composition = 0.0307(7)
Standard Atomic Weight = 150.36(2)
Notes = g

Atomic Number = 62
Atomic Symbol = Sm
Mass Number = 147
Relative Atomic Mass = 146.9149044(19)
Isotopic Composition = 0.1499(18)
Standard Atomic Weight = 150.36(2)
Notes = g

Atomic Number = 62
Atomic Symbol = Sm
Mass Number = 148
Relative Atomic Mass = 147.9148292(19)
Isotopic Composition = 0.1124(10)
Standard Atomic Weight = 150.36(2)
Notes = g

Atomic Number = 62
Atomic Symbol = Sm
Mass Number = 149
Relative Atomic Mass = 148.9171921(18)
Isotopic Composition = 0.1382(7)
Standard Atomic Weight = 150.36(2)
Notes = g

Atomic Number = 62
Atomic Symbol = Sm
Mass Number = 150
Relative Atomic Mass = 149.9172829(18)
Isotopic Composition = 0.0738(1)
Standard Atomic Weight = 150.36(2)
Notes = g

Atomic Number = 62
Atomic Symbol = Sm
Mass Number = 152
Relative Atomic Mass = 151.9197397(18)
Isotopic Composition = 0.2675(16)
Standard Atomic Weight = 150.36(2)
Notes = g

Atomic Number = 62
Atomic Symbol = Sm
Mass Number = 154
Relative Atomic Mass = 153.9222169(20)
Isotopic Composition = 0.2275(29)
Standard Atomic Weight = 150.36(2)
Notes = g

Atomic Number = 63
Atomic Symbol = Eu
Mass Number = 151
Relative Atomic Mass = 150.9198578(18)
Isotopic Composition = 0.4781(6)
Standard Atomic Weight = 151.964(1)
Notes = g

Atomic Number = 63
Atomic Symbol = Eu
Mass Number = 153
Relative Atomic Mass = 152.9212380(18)
Isotopic Composition = 0.5219(6)
Standard Atomic Weight = 151.964(1)
Notes = g

Atomic Number = 64
Atomic Symbol = Gd
Mass Number = 152
Relative Atomic Mass = 151.9197995(18)
Isotopic Composition = 0.0020(1)
Standard Atomic Weight = 157.25(3)
Notes = g

Atomic Number = 64
Atomic Symbol = Gd
Mass Number = 154
Relative Atomic Mass = 153.9208741(17)
Isotopic Composition = 0.0218(3)
Standard Atomic Weight = 157.25(3)
Notes = g

Atomic Number = 64
Atomic Symbol = Gd
Mass Number = 155
Relative Atomic Mass = 154.9226305(17)
Isotopic Composition = 0.1480(12)
Standard Atomic Weight = 157.25(3)
Notes = g

Atomic Number = 64
Atomic Symbol = Gd
Mass Number = 156
Relative Atomic Mass = 155.9221312(17)
Isotopic Composition = 0.2047(9)
Standard Atomic Weight = 157.25(3)
Notes = g

Atomic Number = 64
Atomic Symbol = Gd
Mass Number = 157
Relative Atomic Mass = 156.9239686(17)
Isotopic Composition = 0.1565(2)
Standard Atomic Weight = 157.25(3)
Notes = g

Atomic Number = 64
Atomic Symbol = Gd
Mass Number = 158
Relative Atomic Mass = 157.9241123(17)
Isotopic Composition = 0.2484(7)
Standard Atomic Weight = 157.25(3)
Notes = g

Atomic Number = 64
Atomic Symbol = Gd
Mass Number = 160
Relative Atomic Mass = 159.9270624(18)
Isotopic Composition = 0.2186(19)
Standard Atomic Weight = 157.25(3)
Notes = g

Atomic Number = 65
Atomic Symbol = Tb
Mass Number = 159
Relative Atomic Mass = 158.9253547(19)
Isotopic Composition = 1
Standard Atomic Weight = 158.92535(2)
Notes =  

Atomic Number = 66
Atomic Symbol = Dy
Mass Number = 156
Relative Atomic Mass = 155.9242847(17)
Isotopic Composition = 0.00056(3)
Standard Atomic Weight = 162.500(1)
Notes = g

Atomic Number = 66
Atomic Symbol = Dy
Mass Number = 158
Relative Atomic Mass = 157.9244159(31)
Isotopic Composition = 0.00095(3)
Standard Atomic Weight = 162.500(1)
Notes = g

Atomic Number = 66
Atomic Symbol = Dy
Mass Number = 160
Relative Atomic Mass = 159.9252046(20)
Isotopic Composition = 0.02329(18)
Standard Atomic Weight = 162.500(1)
Notes = g

Atomic Number = 66
Atomic Symbol = Dy
Mass Number = 161
Relative Atomic Mass = 160.9269405(20)
Isotopic Composition = 0.18889(42)
Standard Atomic Weight = 162.500(1)
Notes = g

Atomic Number = 66
Atomic Symbol = Dy
Mass Number = 162
Relative Atomic Mass = 161.9268056(20)
Isotopic Composition = 0.25475(36)
Standard Atomic Weight = 162.500(1)
Notes = g

Atomic Number = 66
Atomic Symbol = Dy
Mass Number = 163
Relative Atomic Mass = 162.9287383(20)
Isotopic Composition = 0.24896(42)
Standard Atomic Weight = 162.500(1)
Notes = g

Atomic Number = 66
Atomic Symbol = Dy
Mass Number = 164
Relative Atomic Mass = 163.9291819(20)
Isotopic Composition = 0.28260(54)
Standard Atomic Weight = 162.500(1)
Notes = g

Atomic Number = 67
Atomic Symbol = Ho
Mass Number = 165
Relative Atomic Mass = 164.9303288(21)
Isotopic Composition = 1
Standard Atomic Weight = 164.93033(2)
Notes =  

Atomic Number = 68
Atomic Symbol = Er
Mass Number = 162
Relative Atomic Mass = 161.9287884(20)
Isotopic Composition = 0.00139(5)
Standard Atomic Weight = 167.259(3)
Notes = g

Atomic Number = 68
Atomic Symbol = Er
Mass Number = 164
Relative Atomic Mass = 163.9292088(20)
Isotopic Composition = 0.01601(3)
Standard Atomic Weight = 167.259(3)
Notes = g

Atomic Number = 68
Atomic Symbol = Er
Mass Number = 166
Relative Atomic Mass = 165.9302995(22)
Isotopic Composition = 0.33503(36)
Standard Atomic Weight = 167.259(3)
Notes = g

Atomic Number = 68
Atomic Symbol = Er
Mass Number = 167
Relative Atomic Mass = 166.9320546(22)
Isotopic Composition = 0.22869(9)
Standard Atomic Weight = 167.259(3)
Notes = g

Atomic Number = 68
Atomic Symbol = Er
Mass Number = 168
Relative Atomic Mass = 167.9323767(22)
Isotopic Composition = 0.26978(18)
Standard Atomic Weight = 167.259(3)
Notes = g

Atomic Number = 68
Atomic Symbol = Er
Mass Number = 170
Relative Atomic Mass = 169.9354702(26)
Isotopic Composition = 0.14910(36)
Standard Atomic Weight = 167.259(3)
Notes = g

Atomic Number = 69
Atomic Symbol = Tm
Mass Number = 169
Relative Atomic Mass = 168.9342179(22)
Isotopic Composition = 1
Standard Atomic Weight = 168.93422(2)
Notes =  

Atomic Number = 70
Atomic Symbol = Yb
Mass Number = 168
Relative Atomic Mass = 167.9338896(22)
Isotopic Composition = 0.00123(3)
Standard Atomic Weight = 173.054(5)
Notes = g

Atomic Number = 70
Atomic Symbol = Yb
Mass Number = 170
Relative Atomic Mass = 169.9347664(22)
Isotopic Composition = 0.02982(39)
Standard Atomic Weight = 173.054(5)
Notes = g

Atomic Number = 70
Atomic Symbol = Yb
Mass Number = 171
Relative Atomic Mass = 170.9363302(22)
Isotopic Composition = 0.1409(14)
Standard Atomic Weight = 173.054(5)
Notes = g

Atomic Number = 70
Atomic Symbol = Yb
Mass Number = 172
Relative Atomic Mass = 171.9363859(22)
Isotopic Composition = 0.2168(13)
Standard Atomic Weight = 173.054(5)
Notes = g

Atomic Number = 70
Atomic Symbol = Yb
Mass Number = 173
Relative Atomic Mass = 172.9382151(22)
Isotopic Composition = 0.16103(63)
Standard Atomic Weight = 173.054(5)
Notes = g

Atomic Number = 70
Atomic Symbol = Yb
Mass Number = 174
Relative Atomic Mass = 173.9388664(22)
Isotopic Composition = 0.32026(80)
Standard Atomic Weight = 173.054(5)
Notes = g

Atomic Number = 70
Atomic Symbol = Yb
Mass Number = 176
Relative Atomic Mass = 175.9425764(24)
Isotopic Composition = 0.12996(83)
Standard Atomic Weight = 173.054(5)
Notes = g

Atomic Number = 71
Atomic Symbol = Lu
Mass Number = 175
Relative Atomic Mass = 174.9407752(20)
Isotopic Composition = 0.97401(13)
Standard Atomic Weight = 174.9668(1)
Notes = g

Atomic Number = 71
Atomic Symbol = Lu
Mass Number = 176
Relative Atomic Mass = 175.9426897(20)
Isotopic Composition = 0.02599(13)
Standard Atomic Weight = 174.9668(1)
Notes = g

Atomic Number = 72
Atomic Symbol = Hf
Mass Number = 174
Relative Atomic Mass = 173.9400461(28)
Isotopic Composition = 0.0016(1)
Standard Atomic Weight = 178.49(2)
Notes =  

Atomic Number = 72
Atomic Symbol = Hf
Mass Number = 176
Relative Atomic Mass = 175.9414076(22)
Isotopic Composition = 0.0526(7)
Standard Atomic Weight = 178.49(2)
Notes =  

Atomic Number = 72
Atomic Symbol = Hf
Mass Number = 177
Relative Atomic Mass = 176.9432277(20)
Isotopic Composition = 0.1860(9)
Standard Atomic Weight = 178.49(2)
Notes =  

Atomic Number = 72
Atomic Symbol = Hf
Mass Number = 178
Relative Atomic Mass = 177.9437058(20)
Isotopic Composition = 0.2728(7)
Standard Atomic Weight = 178.49(2)
Notes =  

Atomic Number = 72
Atomic Symbol = Hf
Mass Number = 179
Relative Atomic Mass = 178.9458232(20)
Isotopic Composition = 0.1362(2)
Standard Atomic Weight = 178.49(2)
Notes =  

Atomic Number = 72
Atomic Symbol = Hf
Mass Number = 180
Relative Atomic Mass = 179.9465570(20)
Isotopic Composition = 0.3508(16)
Standard Atomic Weight = 178.49(2)
Notes =  

Atomic Number = 73
Atomic Symbol = Ta
Mass Number = 180
Relative Atomic Mass = 179.9474648(24)
Isotopic Composition = 0.0001201(32)
Standard Atomic Weight = 180.94788(2)
Notes =  

Atomic Number = 73
Atomic Symbol = Ta
Mass Number = 181
Relative Atomic Mass = 180.9479958(20)
Isotopic Composition = 0.9998799(32)
Standard Atomic Weight = 180.94788(2)
Notes =  

Atomic Number = 74
Atomic Symbol = W
Mass Number = 180
Relative Atomic Mass = 179.9467108(20)
Isotopic Composition = 0.0012(1)
Standard Atomic Weight = 183.84(1)
Notes =  

Atomic Number = 74
Atomic Symbol = W
Mass Number = 182
Relative Atomic Mass = 181.94820394(91)
Isotopic Composition = 0.2650(16)
Standard Atomic Weight = 183.84(1)
Notes =  

Atomic Number = 74
Atomic Symbol = W
Mass Number = 183
Relative Atomic Mass = 182.95022275(90)
Isotopic Composition = 0.1431(4)
Standard Atomic Weight = 183.84(1)
Notes =  

Atomic Number = 74
Atomic Symbol = W
Mass Number = 184
Relative Atomic Mass = 183.95093092(94)
Isotopic Composition = 0.3064(2)
Standard Atomic Weight = 183.84(1)
Notes =  

Atomic Number = 74
Atomic Symbol = W
Mass Number = 186
Relative Atomic Mass = 185.9543628(17)
Isotopic Composition = 0.2843(19)
Standard Atomic Weight = 183.84(1)
Notes =  

Atomic Number = 75
Atomic Symbol = Re
Mass Number = 185
Relative Atomic Mass = 184.9529545(13)
Isotopic Composition = 0.3740(2)
Standard Atomic Weight = 186.207(1)
Notes =  

Atomic Number = 75
Atomic Symbol = Re
Mass Number = 187
Relative Atomic Mass = 186.9557501(16)
Isotopic Composition = 0.6260(2)
Standard Atomic Weight = 186.207(1)
Notes =  

Atomic Number = 76
Atomic Symbol = Os
Mass Number = 184
Relative Atomic Mass = 183.9524885(14)
Isotopic Composition = 0.0002(1)
Standard Atomic Weight = 190.23(3)
Notes = g

Atomic Number = 76
Atomic Symbol = Os
Mass Number = 186
Relative Atomic Mass = 185.9538350(16)
Isotopic Composition = 0.0159(3)
Standard Atomic Weight = 190.23(3)
Notes = g

Atomic Number = 76
Atomic Symbol = Os
Mass Number = 187
Relative Atomic Mass = 186.9557474(16)
Isotopic Composition = 0.0196(2)
Standard Atomic Weight = 190.23(3)
Notes = g

Atomic Number = 76
Atomic Symbol = Os
Mass Number = 188
Relative Atomic Mass = 187.9558352(16)
Isotopic Composition = 0.1324(8)
Standard Atomic Weight = 190.23(3)
Notes = g

Atomic Number = 76
Atomic Symbol = Os
Mass Number = 189
Relative Atomic Mass = 188.9581442(17)
Isotopic Composition = 0.1615(5)
Standard Atomic Weight = 190.23(3)
Notes = g

Atomic Number = 76
Atomic Symbol = Os
Mass Number = 190
Relative Atomic Mass = 189.9584437(17)
Isotopic Composition = 0.2626(2)
Standard Atomic Weight = 190.23(3)
Notes = g

Atomic Number = 76
Atomic Symbol = Os
Mass Number = 192
Relative Atomic Mass = 191.9614770(29)
Isotopic Composition = 0.4078(19)
Standard Atomic Weight = 190.23(3)
Notes = g

Atomic Number = 77
Atomic Symbol = Ir
Mass Number = 191
Relative Atomic Mass = 190.9605893(21)
Isotopic Composition = 0.373(2)
Standard Atomic Weight = 192.217(3)
Notes =  

Atomic Number = 77
Atomic Symbol = Ir
Mass Number = 193
Relative Atomic Mass = 192.9629216(21)
Isotopic Composition = 0.627(2)
Standard Atomic Weight = 192.217(3)
Notes =  

Atomic Number = 78
Atomic Symbol = Pt
Mass Number = 190
Relative Atomic Mass = 189.9599297(63)
Isotopic Composition = 0.00012(2)
Standard Atomic Weight = 195.084(9)
Notes =  

Atomic Number = 78
Atomic Symbol = Pt
Mass Number = 192
Relative Atomic Mass = 191.9610387(32)
Isotopic Composition = 0.00782(24)
Standard Atomic Weight = 195.084(9)
Notes =  

Atomic Number = 78
Atomic Symbol = Pt
Mass Number = 194
Relative Atomic Mass = 193.9626809(10)
Isotopic Composition = 0.3286(40)
Standard Atomic Weight = 195.084(9)
Notes =  

Atomic Number = 78
Atomic Symbol = Pt
Mass Number = 195
Relative Atomic Mass = 194.9647917(10)
Isotopic Composition = 0.3378(24)
Standard Atomic Weight = 195.084(9)
Notes =  

Atomic Number = 78
Atomic Symbol = Pt
Mass Number = 196
Relative Atomic Mass = 195.96495209(99)
Isotopic Composition = 0.2521(34)
Standard Atomic Weight = 195.084(9)
Notes =  

Atomic Number = 78
Atomic Symbol = Pt
Mass Number = 198
Relative Atomic Mass = 197.9678949(23)
Isotopic Composition = 0.07356(130)
Standard Atomic Weight = 195.084(9)
Notes =  

Atomic Number = 79
Atomic Symbol = Au
Mass Number = 197
Relative Atomic Mass = 196.96656879(71)
Isotopic Composition = 1
Standard Atomic Weight = 196.966569(5)
Notes =  

Atomic Number = 80
Atomic Symbol = Hg
Mass Number = 196
Relative Atomic Mass = 195.9658326(32)
Isotopic Composition = 0.0015(1)
Standard Atomic Weight = 200.592(3)
Notes =  

Atomic Number = 80
Atomic Symbol = Hg
Mass Number = 198
Relative Atomic Mass = 197.96676860(52)
Isotopic Composition = 0.0997(20)
Standard Atomic Weight = 200.592(3)
Notes =  

Atomic Number = 80
Atomic Symbol = Hg
Mass Number = 199
Relative Atomic Mass = 198.96828064(46)
Isotopic Composition = 0.1687(22)
Standard Atomic Weight = 200.592(3)
Notes =  

Atomic Number = 80
Atomic Symbol = Hg
Mass Number = 200
Relative Atomic Mass = 199.96832659(47)
Isotopic Composition = 0.2310(19)
Standard Atomic Weight = 200.592(3)
Notes =  

Atomic Number = 80
Atomic Symbol = Hg
Mass Number = 201
Relative Atomic Mass = 200.97030284(69)
Isotopic Composition = 0.1318(9)
Standard Atomic Weight = 200.592(3)
Notes =  

Atomic Number = 80
Atomic Symbol = Hg
Mass Number = 202
Relative Atomic Mass = 201.97064340(69)
Isotopic Composition = 0.2986(26)
Standard Atomic Weight = 200.592(3)
Notes =  

Atomic Number = 80
Atomic Symbol = Hg
Mass Number = 204
Relative Atomic Mass = 203.97349398(53)
Isotopic Composition = 0.0687(15)
Standard Atomic Weight = 200.592(3)
Notes =  

Atomic Number = 81
Atomic Symbol = Tl
Mass Number = 203
Relative Atomic Mass = 202.9723446(14)
Isotopic Composition = 0.2952(1)
Standard Atomic Weight = [204.382,204.385]
Notes =  

Atomic Number = 81
Atomic Symbol = Tl
Mass Number = 205
Relative Atomic Mass = 204.9744278(14)
Isotopic Composition = 0.7048(1)
Standard Atomic Weight = [204.382,204.385]
Notes =  

Atomic Number = 82
Atomic Symbol = Pb
Mass Number = 204
Relative Atomic Mass = 203.9730440(13)
Isotopic Composition = 0.014(1)
Standard Atomic Weight = 207.2(1)
Notes = g,r

Atomic Number = 82
Atomic Symbol = Pb
Mass Number = 206
Relative Atomic Mass = 205.9744657(13)
Isotopic Composition = 0.241(1)
Standard Atomic Weight = 207.2(1)
Notes = g,r

Atomic Number = 82
Atomic Symbol = Pb
Mass Number = 207
Relative Atomic Mass = 206.9758973(13)
Isotopic Composition = 0.221(1)
Standard Atomic Weight = 207.2(1)
Notes = g,r

Atomic Number = 82
Atomic Symbol = Pb
Mass Number = 208
Relative Atomic Mass = 207.9766525(13)
Isotopic Composition = 0.524(1)
Standard Atomic Weight = 207.2(1)
Notes = g,r

Atomic Number = 83
Atomic Symbol = Bi
Mass Number = 209
Relative Atomic Mass = 208.9803991(16)
Isotopic Composition = 1
Standard Atomic Weight = 208.98040(1)
Notes =  

Atomic Number = 84
Atomic Symbol = Po
Mass Number = 209
Relative Atomic Mass = 208.9824308(20)
Isotopic Composition = 
Standard Atomic Weight = [209]
Notes =  

Atomic Number = 84
Atomic Symbol = Po
Mass Number = 210
Relative Atomic Mass = 209.9828741(13)
Isotopic Composition = 
Standard Atomic Weight = [209]
Notes =  

Atomic Number = 85
Atomic Symbol = At
Mass Number = 210
Relative Atomic Mass = 209.9871479(83)
Isotopic Composition = 
Standard Atomic Weight = [210]
Notes =  

Atomic Number = 85
Atomic Symbol = At
Mass Number = 211
Relative Atomic Mass = 210.9874966(30)
Isotopic Composition = 
Standard Atomic Weight = [210]
Notes =  

Atomic Number = 86
Atomic Symbol = Rn
Mass Number = 211
Relative Atomic Mass = 210.9906011(73)
Isotopic Composition = 
Standard Atomic Weight = [222]
Notes =  

Atomic Number = 86
Atomic Symbol = Rn
Mass Number = 220
Relative Atomic Mass = 220.0113941(23)
Isotopic Composition = 
Standard Atomic Weight = [222]
Notes =  

Atomic Number = 86
Atomic Symbol = Rn
Mass Number = 222
Relative Atomic Mass = 222.0175782(25)
Isotopic Composition = 
Standard Atomic Weight = [222]
Notes =  

Atomic Number = 87
Atomic Symbol = Fr
Mass Number = 223
Relative Atomic Mass = 223.0197360(25)
Isotopic Composition = 
Standard Atomic Weight = [223]
Notes =  

Atomic Number = 88
Atomic Symbol = Ra
Mass Number = 223
Relative Atomic Mass = 223.0185023(27)
Isotopic Composition = 
Standard Atomic Weight = [226]
Notes =  

Atomic Number = 88
Atomic Symbol = Ra
Mass Number = 224
Relative Atomic Mass = 224.0202120(23)
Isotopic Composition = 
Standard Atomic Weight = [226]
Notes =  

Atomic Number = 88
Atomic Symbol = Ra
Mass Number = 226
Relative Atomic Mass = 226.0254103(25)
Isotopic Composition = 
Standard Atomic Weight = [226]
Notes =  

Atomic Number = 88
Atomic Symbol = Ra
Mass Number = 228
Relative Atomic Mass = 228.0310707(26)
Isotopic Composition = 
Standard Atomic Weight = [226]
Notes =  

Atomic Number = 89
Atomic Symbol = Ac
Mass Number = 227
Relative Atomic Mass = 227.0277523(25)
Isotopic Composition = 
Standard Atomic Weight = [227]
Notes =  

Atomic Number = 90
Atomic Symbol = Th
Mass Number = 230
Relative Atomic Mass = 230.0331341(19)
Isotopic Composition = 
Standard Atomic Weight = 232.0377(4)
Notes = g

Atomic Number = 90
Atomic Symbol = Th
Mass Number = 232
Relative Atomic Mass = 232.0380558(21)
Isotopic Composition = 1
Standard Atomic Weight = 232.0377(4)
Notes = g

Atomic Number = 91
Atomic Symbol = Pa
Mass Number = 231
Relative Atomic Mass = 231.0358842(24)
Isotopic Composition = 1
Standard Atomic Weight = 231.03588(2)
Notes =  

Atomic Number = 92
Atomic Symbol = U
Mass Number = 233
Relative Atomic Mass = 233.0396355(29)
Isotopic Composition = 
Standard Atomic Weight = 238.02891(3)
Notes = g,m

Atomic Number = 92
Atomic Symbol = U
Mass Number = 234
Relative Atomic Mass = 234.0409523(19)
Isotopic Composition = 0.000054(5)
Standard Atomic Weight = 238.02891(3)
Notes = g,m

Atomic Number = 92
Atomic Symbol = U
Mass Number = 235
Relative Atomic Mass = 235.0439301(19)
Isotopic Composition = 0.007204(6)
Standard Atomic Weight = 238.02891(3)
Notes = g,m

Atomic Number = 92
Atomic Symbol = U
Mass Number = 236
Relative Atomic Mass = 236.0455682(19)
Isotopic Composition = 
Standard Atomic Weight = 238.02891(3)
Notes = g,m

Atomic Number = 92
Atomic Symbol = U
Mass Number = 238
Relative Atomic Mass = 238.0507884(20)
Isotopic Composition = 0.992742(10)
Standard Atomic Weight = 238.02891(3)
Notes = g,m

Atomic Number = 93
Atomic Symbol = Np
Mass Number = 236
Relative Atomic Mass = 236.046570(54)
Isotopic Composition = 
Standard Atomic Weight = [237]
Notes =  

Atomic Number = 93
Atomic Symbol = Np
Mass Number = 237
Relative Atomic Mass = 237.0481736(19)
Isotopic Composition = 
Standard Atomic Weight = [237]
Notes =  

Atomic Number = 94
Atomic Symbol = Pu
Mass Number = 238
Relative Atomic Mass = 238.0495601(19)
Isotopic Composition = 
Standard Atomic Weight = [244]
Notes =  

Atomic Number = 94
Atomic Symbol = Pu
Mass Number = 239
Relative Atomic Mass = 239.0521636(19)
Isotopic Composition = 
Standard Atomic Weight = [244]
Notes =  

Atomic Number = 94
Atomic Symbol = Pu
Mass Number = 240
Relative Atomic Mass = 240.0538138(19)
Isotopic Composition = 
Standard Atomic Weight = [244]
Notes =  

Atomic Number = 94
Atomic Symbol = Pu
Mass Number = 241
Relative Atomic Mass = 241.0568517(19)
Isotopic Composition = 
Standard Atomic Weight = [244]
Notes =  

Atomic Number = 94
Atomic Symbol = Pu
Mass Number = 242
Relative Atomic Mass = 242.0587428(20)
Isotopic Composition = 
Standard Atomic Weight = [244]
Notes =  

Atomic Number = 94
Atomic Symbol = Pu
Mass Number = 244
Relative Atomic Mass = 244.0642053(56)
Isotopic Composition = 
Standard Atomic Weight = [244]
Notes =  

Atomic Number = 95
Atomic Symbol = Am
Mass Number = 241
Relative Atomic Mass = 241.0568293(19)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 95
Atomic Symbol = Am
Mass Number = 243
Relative Atomic Mass = 243.0613813(24)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 96
Atomic Symbol = Cm
Mass Number = 243
Relative Atomic Mass = 243.0613893(22)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 96
Atomic Symbol = Cm
Mass Number = 244
Relative Atomic Mass = 244.0627528(19)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 96
Atomic Symbol = Cm
Mass Number = 245
Relative Atomic Mass = 245.0654915(22)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 96
Atomic Symbol = Cm
Mass Number = 246
Relative Atomic Mass = 246.0672238(22)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 96
Atomic Symbol = Cm
Mass Number = 247
Relative Atomic Mass = 247.0703541(47)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 96
Atomic Symbol = Cm
Mass Number = 248
Relative Atomic Mass = 248.0723499(56)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 97
Atomic Symbol = Bk
Mass Number = 247
Relative Atomic Mass = 247.0703073(59)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 97
Atomic Symbol = Bk
Mass Number = 249
Relative Atomic Mass = 249.0749877(27)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 98
Atomic Symbol = Cf
Mass Number = 249
Relative Atomic Mass = 249.0748539(23)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 98
Atomic Symbol = Cf
Mass Number = 250
Relative Atomic Mass = 250.0764062(22)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 98
Atomic Symbol = Cf
Mass Number = 251
Relative Atomic Mass = 251.0795886(48)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 98
Atomic Symbol = Cf
Mass Number = 252
Relative Atomic Mass = 252.0816272(56)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 99
Atomic Symbol = Es
Mass Number = 252
Relative Atomic Mass = 252.082980(54)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 100
Atomic Symbol = Fm
Mass Number = 257
Relative Atomic Mass = 257.0951061(69)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 101
Atomic Symbol = Md
Mass Number = 258
Relative Atomic Mass = 258.0984315(50)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 101
Atomic Symbol = Md
Mass Number = 260
Relative Atomic Mass = 260.10365(34#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 102
Atomic Symbol = No
Mass Number = 259
Relative Atomic Mass = 259.10103(11#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 103
Atomic Symbol = Lr
Mass Number = 262
Relative Atomic Mass = 262.10961(22#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 104
Atomic Symbol = Rf
Mass Number = 267
Relative Atomic Mass = 267.12179(62#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 105
Atomic Symbol = Db
Mass Number = 268
Relative Atomic Mass = 268.12567(57#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 106
Atomic Symbol = Sg
Mass Number = 271
Relative Atomic Mass = 271.13393(63#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 107
Atomic Symbol = Bh
Mass Number = 272
Relative Atomic Mass = 272.13826(58#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 108
Atomic Symbol = Hs
Mass Number = 270
Relative Atomic Mass = 270.13429(27#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 109
Atomic Symbol = Mt
Mass Number = 276
Relative Atomic Mass = 276.15159(59#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 110
Atomic Symbol = Ds
Mass Number = 281
Relative Atomic Mass = 281.16451(59#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 111
Atomic Symbol = Rg
Mass Number = 280
Relative Atomic Mass = 280.16514(61#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 112
Atomic Symbol = Cn
Mass Number = 285
Relative Atomic Mass = 285.17712(60#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 113
Atomic Symbol = Nh
Mass Number = 284
Relative Atomic Mass = 284.17873(62#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 114
Atomic Symbol = Fl
Mass Number = 289
Relative Atomic Mass = 289.19042(60#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 115
Atomic Symbol = Mc
Mass Number = 288
Relative Atomic Mass = 288.19274(62#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 116
Atomic Symbol = Lv
Mass Number = 293
Relative Atomic Mass = 293.20449(60#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 117
Atomic Symbol = Ts
Mass Number = 292
Relative Atomic Mass = 292.20746(75#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

Atomic Number = 118
Atomic Symbol = Og
Mass Number = 294
Relative Atomic Mass = 294.21392(71#)
Isotopic Composition = 
Standard Atomic Weight =  
Notes =  

NIST | Physical Measurement Laboratory | Physical Reference Data | Atomic Weights and Isotopic Compositions Main Page