Question

chromium crystalles in bcc stuctre .if its edge lenght is 300pm' find its density Atomic mass of chromium is 52 u.NA=6.022x10'23mol-1​

Answer 1

Answer : 7.30gcm−3

In a body-centred cubic lattice ,atoms touch each other along the body-diagonal of the cube.Hence

4r=3–√a or r=3–√a4=(1.732)(287pm)4=124.27pm.

The expression of density is ρ=Na3(MNA)

Substituting the values,we get

ρ=2(287×10−10cm)3(51.99gmol−16.023×1023mol−1)=7.30gcm−3