An elemental crystal has a density of 8570 k g / m 3 . The packing efficiency is 0.68. The closest distance of approach between neighbouring atom is 2.86 Å . What is the mass in amu of one atom approximately? [Report your answer by rounding it upto nearset whole number]

Step-by-step solution

The p a c k i n g e f f i c i e n c y = 0.68 , means the given lattice is B C C . The closest distance of a p p r o a c h = 2 r 2 r = 2.86 A o = 3 a 2 ⇒ 2 × 2.86 3 = 3.30 A o . Let, at. wt. of the e l e m e n t = w ∴ 2 ×w 6 × 1 0 23 × 3.3 3 × 1 0 – 30 = 8570 w = 92.39   ≃   93 amu