Question

The length of the unit cell edge of a body-centred cubic metal crystal is 352pm.Calculate the radius of an atom of the metal.

Answer 1

Answer:

Let radius of an atom be r.

Now if edge length is a, then length of diagonal of a face is √a2+a2 = a√2

So, length of the diagonal of whole cube becomes √(a√2)2+a2 = a√3.

Since, atoms touch each other to accommodate in the cell, then for BCC, 4r = a√3

So, r = √3/4. a

So, radius, r = √3/4 × 352 = 88√3pm = 152.42pm