Question

Determine the structure and coordination number of MgS on the basis of radius ratio in which radius of Mg²⁺ and S^2– is 65 pm and 184 pm respectively. 

Answer 1

Given: Radius of cation Mg²⁺ (r+ ) = 65 pm 

Radius of anion S²⁻ (r⁻ ) = 184 pm

To find: i. The coordination number of MgS = ?

ii. Structure of MgS = ?

Formula: 

Radius ratio = Radius of the cation/ Radius of the anion

Calculation: 

From formula,

Since the radius ratio lies in between 0.225 – 0.414 

The coordination number of MgS is 4. And the structure of MgS is Tetrahedral.