Question

The total number of atoms in one unit cell of primitive unit cubic cell is ______ atom(s).

(a) 1

(b) 8

(c) 4

(d) 2

I had been asked this question by my college professor while I was bunking the class.

My question is taken from Solid State topic in portion Solid State of Chemistry – Class 12

Answer 1

Right choice is (a) 1

Best explanation: In primitive cubic unit cell, atoms are present only at the corner of the cell. Thus, in actual, only \(\frac{1}{8}\)th of an atom (or ion or molecule) belongs to a particular unit cell. Hence, the total number of atoms in primitive cubic unit cell = 8 × \(\frac{1}{8}\) = 1 atom.