Question

If metallic radius of metal having $fcc$ structure is $127pm$, then the length of edge of its unit cell will be.

• A. $288pm$
• B. $359pm$
• C. $576pm$
• D. $432pm$

Answer 1

The correct option is B $359pm$

In FCC unit cell

$4r=a\sqrt{2}$ (along the face diagonal)

$a=2\sqrt{2}r$

$a=2\sqrt{2}\times 127=359$ $pm$