Question

An element has a primitive cubic structure with unit cell edge length of $272\text{pm}$. The atomic radius is:

• A. $\frac{\sqrt{2}}{4}\times 272\text{pm}$
• B. $\frac{4}{\sqrt{3}}\times 272\text{pm}$
• C. $\frac{1}{\sqrt{2}}\times 272\text{pm}$
• D. $\frac{1}{2}\times 272\text{pm}$

Answer 1

The correct option is D $\frac{1}{2}\times 272\text{pm}$

In primitive cubic lattice, $a=2r$

$\therefore r=\frac{a}{2}$
$r=272\times \frac{1}{2}\text{pm}$