Question

Sodium metal crystallizes in body-centered cubic lattice with the cell edge (a) = $4.29\mathring{A}$ .The radius of sodium atom is (in $\mathring{A}$):

Answer 1

Given that sodium metal crystallises in body-centred cubic lattice.

For bcc lattice,
$r=\frac{\sqrt{3}a}{4}=\frac{\sqrt{3}\times 4.29}{4}=1.957\mathring{A}$

Hence, the radius of sodium atom is $1.957\mathring{A}$.