Question

A crystalline solid of a pure substance has a face-centred cubic structure with a cell edge of 400 pm. If the
density of the substance in the crystal is 8 g cm⁻³, then the number of atoms present in 256 g of the crystal is N × 10²⁴. The value of N is

Answer 1

Answer:

The edge length a = 400 pm = 400 × 10-10 cm The formula for the density is D = ZMN0a3 8 g/cm3 = 4 atoms M6.023 × 1023 atoms/mol × (400 × 10-10 ...