A cubic unit cell has atoms only at the corners. What is the total number of atoms per unit cell?
1
2
4
8
In a cubic unit cell with atoms only at the corners, each corner atom is shared equally between 8 adjacent unit cells. Therefore, the contribution of each corner atom to the unit cell is .
Number of corner atoms in a unit cell = 8
Contribution of each corner atom to the unit cell =
Total number of atoms per unit cell =
Therefore, the correct answer is (c) 4, as there are 4 corner atoms in a cubic unit cell with atoms only at the corners.