Question

A solid AB has NaCl type structure. The radius of A is 100 pm. What is the radius of B ?

(a) 190.47

(b) 540.13

(c) 525

(d) 78.12

Answer 1

Correct option (a) 190.47

Explanation:

NaCl type structure has face-centred cubic lattice. Here the radius ratio (r_c/r_c) ranges from 0.414 to 0.732.

radius ratio  = r_c/r_c = radius of cation/ radius of anion

= radius of anion (B^-) = radius of A⁺/radius of ratio

= 100/0.414 to 100/0.732

= 241.5 to 136.6