Hvor ligger atomvægten på det periodiske system?
Template:Periodic table (standard atomic weight)
Standardatomvægt (forkortet, konventionel*)


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Gruppe →


↓ Periode


1
H 7000100800000000000♠1.008

He7000400260000000000♠4.0026


2
Li7000694000000000000♠6.94
Be7000901220000000000♠9.0122

B 7001108100000000000♠10.81
C 7001120110000000000♠12.011
N 7001140070000000000♠14.007
O 7001159990000000000♠15.999
F 7001189980000000000♠18.998
Ne7001201800000000000♠20.180


3
Na7001229899999999999♠22.990
Mg7001243050000000000♠24.305

Al7001269820000000000♠26.982
Si7001280850000000000♠28.085
P 7001309740000000000♠30.974
S 7001320600000000000♠32.06
Cl7001354500000000000♠35.45
Ar7001399480000000000♠39.948


4
K 7001390980000000000♠39.098
Ca7001400780000000000♠40.078(4)
Sc7001449560000000000♠44.956

Ti7001478670000000000♠47.867
V 7001509420000000000♠50.942
Cr7001519960000000000♠51.996
Mn7001549380000000000♠54.938
Fe7001558450000000000♠55.845(2)
Co7001589330000000000♠58.933
Ni7001586930000000000♠58.693
Cu7001635460000000000♠63.546(3)
Zn7001653800000000000♠65.38(2)
Ga7001697230000000000♠69.723
Ge7001726300000000000♠72.630(8)
As7001749220000000000♠74.922
Se7001789710000000000♠78.971(8)
Br7001799040000000000♠79.904
Kr7001837980000000000♠83.798(2)


5
Rb7001854680000000000♠85.468
Sr7001876200000000000♠87.62
Y 7001889060000000000♠88.906

Zr7001912240000000000♠91.224(2)
Nb7001929060000000000♠92.906
Mo7001959500000000000♠95.95
Tc
Ru7002101070000000000♠101.07(2)
Rh7002102910000000000♠102.91
Pd7002106420000000000♠106.42
Ag7002107870000000000♠107.87
Cd7002112410000000000♠112.41
In7002114820000000000♠114.82
Sn7002118710000000000♠118.71
Sb7002121760000000000♠121.76
Te7002127600000000000♠127.60(3)
I 7002126900000000000♠126.90
Xe7002131289999999999♠131.29


6
Cs7002132910000000000♠132.91
Ba7002137330000000000♠137.33
La7002138910000000000♠138.91

Hf7002178490000000000♠178.49(2)
Ta7002180950000000000♠180.95
W 7002183840000000000♠183.84
Re7002186210000000000♠186.21
Os7002190230000000000♠190.23(3)
Ir7002192220000000000♠192.22
Pt7002195080000000000♠195.08
Au7002196970000000000♠196.97
Hg7002200590000000000♠200.59
Tl7002204380000000000♠204.38
Pb7002207200000000000♠207.2
Bi7002208980000000000♠208.98
Po
På
Rn


7
Fr
Ra
Ac

Rf
Db
Sg
Bh
Hs
Mt
Ds
Rg
Cn
Nh
Fl
Mc
Lv
Ts
Og






Ce7002140120000000000♠140.12
Pr7002140910000000000♠140.91
Nd7002144240000000000♠144.24
Pm
Sm7002150360000000000♠150.36(2)
Eu7002151960000000000♠151.96
Gd7002157250000000000♠157.25(3)
Tb7002158930000000000♠158.93
Dy7002162500000000000♠162.50
Ho7002164930000000000♠164.93
Er7002167260000000000♠167.26
Tm7002168930000000000♠168.93
Yb7002173050000000000♠173.05
Lu7002174970000000000♠174.97



Th7002232040000000000♠232.04
Pa7002231040000000000♠231.04
U 7002238030000000000♠238.03
Np
Pu
Am
Cm
Bk
Cf
Es
Fm
Md
Nej
Lr


 * Standardatomvægt
Den formelle standardatomvægt kan se ud som 4,002602(2) for helium og [1,0078, 1,0082] for brint. "(n)" er usikkerheden.


   Forkortet
Værdien er forkortet til fem betydende cifre. ±-usikkerheden angives som "(x)", eller "(1)", hvis den ikke er angivet. Se forkortet standardatomvægt.


   Konventionel
Når den formelle standardatomvægt er et interval, som f.eks. [1,0078, 1,0082], offentliggøres også et enkelt enkelt tal. Se konventionel standardatomvægt.


 * Massetal
Ustabile grundstoffer har ikke en standardatomvægt. De har det viste massetal for den mest stabile isotop (formateret ).
Template:Periodic table (standard atomic weight)
Standard atomic weight (abridged, conventional*)


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Group →


↓ Period


1
H 7000100800000000000♠1.008

He7000400260000000000♠4.0026


2
Li7000694000000000000♠6.94
Be7000901220000000000♠9.0122

B 7001108100000000000♠10.81
C 7001120110000000000♠12.011
N 7001140070000000000♠14.007
O 7001159990000000000♠15.999
F 7001189980000000000♠18.998
Ne7001201800000000000♠20.180


3
Na7001229899999999999♠22.990
Mg7001243050000000000♠24.305

Al7001269820000000000♠26.982
Si7001280850000000000♠28.085
P 7001309740000000000♠30.974
S 7001320600000000000♠32.06
Cl7001354500000000000♠35.45
Ar7001399480000000000♠39.948


4
K 7001390980000000000♠39.098
Ca7001400780000000000♠40.078(4)
Sc7001449560000000000♠44.956

Ti7001478670000000000♠47.867
V 7001509420000000000♠50.942
Cr7001519960000000000♠51.996
Mn7001549380000000000♠54.938
Fe7001558450000000000♠55.845(2)
Co7001589330000000000♠58.933
Ni7001586930000000000♠58.693
Cu7001635460000000000♠63.546(3)
Zn7001653800000000000♠65.38(2)
Ga7001697230000000000♠69.723
Ge7001726300000000000♠72.630(8)
As7001749220000000000♠74.922
Se7001789710000000000♠78.971(8)
Br7001799040000000000♠79.904
Kr7001837980000000000♠83.798(2)


5
Rb7001854680000000000♠85.468
Sr7001876200000000000♠87.62
Y 7001889060000000000♠88.906

Zr7001912240000000000♠91.224(2)
Nb7001929060000000000♠92.906
Mo7001959500000000000♠95.95
Tc
Ru7002101070000000000♠101.07(2)
Rh7002102910000000000♠102.91
Pd7002106420000000000♠106.42
Ag7002107870000000000♠107.87
Cd7002112410000000000♠112.41
In7002114820000000000♠114.82
Sn7002118710000000000♠118.71
Sb7002121760000000000♠121.76
Te7002127600000000000♠127.60(3)
I 7002126900000000000♠126.90
Xe7002131289999999999♠131.29


6
Cs7002132910000000000♠132.91
Ba7002137330000000000♠137.33
La7002138910000000000♠138.91

Hf7002178490000000000♠178.49(2)
Ta7002180950000000000♠180.95
W 7002183840000000000♠183.84
Re7002186210000000000♠186.21
Os7002190230000000000♠190.23(3)
Ir7002192220000000000♠192.22
Pt7002195080000000000♠195.08
Au7002196970000000000♠196.97
Hg7002200590000000000♠200.59
Tl7002204380000000000♠204.38
Pb7002207200000000000♠207.2
Bi7002208980000000000♠208.98
Po
At
Rn


7
Fr
Ra
Ac

Rf
Db
Sg
Bh
Hs
Mt
Ds
Rg
Cn
Nh
Fl
Mc
Lv
Ts
Og






Ce7002140120000000000♠140.12
Pr7002140910000000000♠140.91
Nd7002144240000000000♠144.24
Pm
Sm7002150360000000000♠150.36(2)
Eu7002151960000000000♠151.96
Gd7002157250000000000♠157.25(3)
Tb7002158930000000000♠158.93
Dy7002162500000000000♠162.50
Ho7002164930000000000♠164.93
Er7002167260000000000♠167.26
Tm7002168930000000000♠168.93
Yb7002173050000000000♠173.05
Lu7002174970000000000♠174.97



Th7002232040000000000♠232.04
Pa7002231040000000000♠231.04
U 7002238030000000000♠238.03
Np
Pu
Am
Cm
Bk
Cf
Es
Fm
Md
No
Lr


 * Standard atomic weight
The formal standard atomic weight may look like 4.002602(2) for helium, and [1.0078, 1.0082] for hydrogen. The "(n)" is the uncertainty.


   Abridged
The value is abridged to five significant figures. The ± uncertainty is noted as "(x)", or "(1)" when omitted. See abridged standard atomic weight.


   Conventional
When the formal standard atomic weight is an interval, like [1.0078, 1.0082], a simple, single number is published too. See conventional standard atomic weight.


 * Mass number
Unstable elements do not have a standard atomic weight. These have the mass number shown of the most stable isotope (formatted ).
Template:Periodic table (standard atomic weight)