Question

If the valency of an element is 2, then it lies in group

Answer 1

Atomic number (Z)=15=P→[Ne]3s23p3

Phosphorus belongs to 15th group 

number of valence electrons 3s23p3=5

and valency =3 in ground state.

Hence, the correct option is C

Answer 2

Explanation:

Valency of First 30 Elements

Element Atomic Number Valency

Valency of Hydrogen 1 1

Valency of Helium 2 0

Valency of Lithium 3 1

Valency of Beryllium 4 2