An element crystallises bcc type of unit cell, the density and edge length of unit cell is 4 ~g ~cm ⁻³ and 500 pm respectively. What is the atomic mass of an element?

Step-by-step solution

In bcc, n =2, =4 ~g ~cm ⁻³ a =500 pm =500 10⁻¹⁰ ~cm =5 10⁻⁸ ~cm Volume of unit cell, a ³= (5 10⁻⁸ ~cm )³=125 10⁻²⁴ ~cm ³ Now, M = a ³ N _ A n = 4 125 10⁻²⁴ 6.022 10²³ 2 =150.5 ~g ~mol ⁻¹