Lithium forms body centred cubic structure. The length of the side of its unit cell is 351 pm. Atomic radius of the lithium will be.

Options

A. 300 pm
B. 240 pm
C. 152 pm
D. 75 pm

Answer

C

Explanation

a = 351 pm
For bcc unit cell, `a sqrt(3)=4r`
`r=(a sqrt(3))/(4)=(351xxsqrt(3))/(4)=152` pm
Thus neglecting `a//v^(2)` gives
`P(V-b)=RT` or `PV=RT+Pb`
or `(PV)/(RT)=Z=(RT+Pb)/(RT)rArr Z=1+Pb//RT`