Ga (atomic mass 70 u) crystallizes in a hexagonal close packed structure. The total number of voids in 0.581 g of Ga is __________ $\times$ 1021. (Round off to the Nearest Integer). [Given : NA = 6.023 $\times$ 1023]
Answer (integer)
15
Solution
For HCP structure Z = 6<br><br>Tetrahedral Void = (Z $\times$ 2) = 12<br><br>Octahedral Void = [Z $\times$ 1] = 6<br><br>No. of void per unit cell = 18<br><br>No. of unit cell = $\left( {{{0.581 \times {N_A}} \over {70 \times 6}}} \right)$<br><br>No. of void = $$\left( {{{0.581 \times 6.023 \times {{10}^{23}}} \over {70 \times 6}}} \right) \times 18$$<br><br>$= 14.99 \times {10^{21}}$
About this question
Subject: Chemistry · Chapter: States of Matter · Topic: Gas Laws
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