How many time atoms are in one unit cell of polonium ?

Options

A. `4`
B. `1`
C. `2`
D. `5`

Answer

2

Explanation

Polonium a radioactive element (At .no. `84`) crystallizes in primitive cubic lattice.In primitive -cubic unit cell there is an atom at each of the eight corners.
When unit cell are stacked together, each cornor atom is shared by eight cubes so that only `1//8` of each atoms "belongs" to a given unit cell. Thus there is `1//8 xx8=1` atom per unit cell.