JEE PYQ: Solid State Question 2
Question 2 - 2021 (16 Mar Shift 2)
Ga (atomic mass 70 u) crystallizes in a hexagonal close packed structure. The total number of voids in 0.581 g of Ga is ___ $\times 10^{21}$. (Round off to the Nearest Integer).
Show Answer
Answer: 15
Solution
HCP structure: per atom, there is one octahedral void (OV) and two tetrahedral voids (TV). Total three voids per atom. Total no. of atoms of Ga $= \dfrac{0.581}{70} \times 6.023 \times 10^{23}$. Total number of voids $= 3 \times \dfrac{0.581}{70} \times 6.023 \times 10^{23} = 14.99 \times 10^{21} \simeq 15 \times 10^{21}$.
BETA
