Question

Calcium crystallizes in fcc structure. Radius of the atom in the metal is 141.4pm. (i) what is the length of the side of the unit cell? (ii) How many atoms of calcium are there in its 5cm3?

Answer 1

Explanation:

Answer

Given, cell is FCC, z=4

Edge length, a=404pm=4.04×10−8cm

Density of metal, d=2.72gcm−3

NA=6.02×1023mol−1

Mass of the metal, M=?

We know,

d=a3×NAz×M

M=zd×NA×a3

M=42.72×(4.04×10−8)3×6.02×1023

Mass, M=27g mol−1