MHT CET Chemistry Question (2026) — Solution

Step-by-step solution

For a simple cubic unit cell, the relation between edge length a and atomic radius r is a = 2r. The number of atoms per unit cell is Z = 1. Volume of the unit cell, V = a^3 = (3.36 10^ -8 )^3 = 37.933 10^ -24 cm ^3 = 3.7933 10^ -23 cm ^3. Volume occupied by the atom = 4 3 r^3 = 4 3 ( a 2 )^3 = 6 a^3. Packing fraction = Volume occupied Total volume = 6 0.5236. Fraction of void volume = 1 - 0.5236 = 0.4764. Void volume = 0.4764 V = 0.4764 3.7933 10^ -23 cm ^3 1.807 10^ -23 cm ^3. Answer: 1.807 10^ -23 cm^3.