Question

How will you find the valency of chlorine, sulphur and magnesium?

Answer 1

The atomic number of chlorine = 17

Number of electrons in chlorine atom = 17

Electron distribution

K	L	M
2	8	7

One electron is required to get into the last shell M of chlorine, which has a valency of 1.

The atomic number of sulphur = 16

Number of electrons in sulphur atom = 16

Internal electron distribution

K	L	M
2	8	6

Two electrons are required to get an electron in the last shell M of sulphur, which has a valency of 2.

The atomic number of magnesium = 12

Number of electrons in magnesium atom = 17

Internal electron distribution

K	L	M
2	8	2

Two electrons are required to get an electron in the last shell M of magnesium, which has a valency of 2.