Question

First 20 elements list with valency and atomic number

Answer 1

A.N wise valency

Hydrogen 1

Helium. 0

Lithium 1

Beriliym. 2

Boron. 3

Carbon. 4

Nitrogen. 3

Oxygen. 2

Fluroine. 1

Neon. 0.

Sodiom 1

Magnesium. 2

Aluminum. 3

Silicon. 4

Phosphorus. 3

Sulphur. 2

Pottasium. 1

Calcium. 2