Question

If elements A and R are placed in group 2 of modern periodic table. If the  valency of element A is 2, the valency of  element R will be​

Answer 1

Atomic number (Z)=15=P→[Ne]3s  

2

3p  

3

 

Phosphorus belongs to 15th group  

number of valence electrons 3s  

2

3p  

3

=5

and valency =3 in ground state.

Hence, the correct option is C