Question

The radius of the Na+ is 95 pm and that of Cl– ion is 181 pm. Predict the coordination number of Na+ .

(A) 4

(B) 6

(C) 8

(D) Unpredictable

Answer 1

Correct option: (B) 6

Explanation:

radius ratio = r+ / r- = 95 / 181 = 0.52

Since the radius ratio is in between 0.414 to 0.732, the coordination number of cation is 6.