Question

The edge length of unit cell of a metal, having molecular weight 75 g/mol is 5Å, which crystallizes in cubic lattice. If the density is 2 g/cc, then find the radius of metal atom. (N_A = 6 x 10²³ mol^-1). Give the answer in pm.

Answer 1

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^. .  Z = 2

Since the number of atoms per unit cell is 2, it indicates that the metal has body centred cubic (bcc) lattice. 

For bcc lattice, body diagonal of the unit cell

d = 2r