Gold crystallizes with FCC lattice for which the side length of the unit cell is Å. If the density o — Solid State Chemistry Question

💡 Solution & Explanation

Density $d = \frac{Z \times M}{N_A \times a^3} \implies 10.5 = \frac{4 \times 198}{N_A \times (5.0 \times 10^{-8})^3} \implies N_A = \frac{792}{10.5 \times 125 \times 10^{-24}} = \frac{792}{1312.5 \times 10^{-24}} = 6.034 \times 10^{23}$. Therefore, correct answer is B.