Question

An element 'X' (At. mass = 40 g mol^-1) having f.c.c. structure, has unit cell edge length of 400 pm. Calculate the density of 'X' and the number of unit cells in 4 g of 'X'. (N₄ = 6.022 x 10²³ mol^-1).

Answer 1

Here, Z = 4, a = 400pm = 4x10^-8 cm, M = 40