# A solid AB has NaCl structure. If the radius of cation A is 110 pm, what is the possible radius of anion B ?

A solid AB has NaCl structure. If the radius of cation A is 110 pm, what is the possible radius of anion B ?

Given Values

Radius of Cation (r+) = 110 pm

Structure of Solid = NaCl type

NaCl type Means: The radius ratio is between 0.414 – 0.732

Calculations

$$\frac{Radius~of~Cation}{Radius~of~Anion}$$ = 0.414 to 0.732

Calculate the maximum possible radius of Anion ‘B’

$$\frac{110}{Radius~of~Anion}=0.414$$

$$Radius~of~Anion = \frac{110}{0.414}$$ = 365.7 pm

Calculate the minimum possible radius of Anion ‘B’

$$\frac{110}{Radius~of~Anion}=0.732$$

$$Radius~of~Anion = \frac{110}{0.732}$$ = 150.27 pm

Therefore, the possible radius of anion ‘B’ is 150.27 pm to 365.7 pm