Question

A cubic structure of uniform spheres has the unit cell edge length of 0.8 nm. If the radius of the molecule in bcc lattice is $34\times {10}^{-x}$, then what is the value of x?

Answer 1

As we know, for bcc lattice,

$r=\frac{\sqrt{3}a}{4}=\frac{\sqrt{3}\times 0.8}{4}=0.3463nm$

$r=34\times {10}^{-2}nm$

By comparing, $r=34\times {10}^{-x}=34\times {10}^{-2}nm$

We get, $x=2$

Hence, the correct answer is $2$.