Valency is the combining power of an element, which determines the number of electrons that an atom can gain, lose, or share when it forms chemical bonds.
Here are the valencies
of some common metals and non-metals:
|
Metals |
Symbol |
Valency |
Non-metals |
Symbol |
Valency |
|
Sodium |
Na |
1 |
Hydrogen |
H |
1 |
|
Potassium |
K |
1 |
Carbon |
C |
4 |
|
Calcium |
Ca |
2 |
Nitrogen |
N |
3, 5 |
|
Magnesium |
Mg |
2 |
Oxygen |
O |
2 |
|
Aluminium |
Al |
3 |
Fluorine |
F |
1 |
|
Iron |
Fe |
2, 3 |
Chlorine |
Cl |
1, 3, 5, 7 |
|
Copper |
Cu |
1, 2 |
Bromine |
Br |
1, 3, 5, 7 |
|
Zinc |
Zn |
2 |
Iodine |
I |
1 |
|
Silver |
Ag |
1 |
Phosphorus |
P |
3, 5 |
|
Gold |
Au |
1, 3 |
Sulphur |
S |
2, 4, 6 |
|
Tin |
Sn |
2, 4 |
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Lead |
Pb |
2, 4 |
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Mercury |
Hg |
1, 2 |
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Cobalt |
Co |
2, 3 |
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Manganese |
Mn |
2, 3, 4, 6, 7 |
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Barium |
Ba |
2 |
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Lithium |
Li |
1 |
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