Definitions
- Valency is the combining power of an element. It is governed by the number of electrons in the outermost electronic shell of the atoms of that element.
- Valence, also known as valency or valency number, is a measure of the number of chemical bonds formed by the atoms of a given element.
- Valency is the numerical value of the charge on an ion (cation or anion), describing the number of bonds which can be formed by the ion.
Some Examples
| Element | Valency |
| Hydrogen | 1 |
| Chlorine | 1 |
| Copper | 1, 2 |
| Calcium | 2 |
| Oxygen | 2 |
| Iron | 2, 3 |
| Tin | 2, 4 |
| Nitrogen | 3 |
| Phosphorus | 3, 5 |
| Carbon | 4 |
| Sulfur | 4, 6 |
