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NEET levelSingle correct optionDifficulty 1 of 3ss008

The percentage of space occupied by atoms in a bcc structure is about

A48%
B68%
C74%
D52%

Answer: B

In bcc

3 a = 4 r

and

Z = 2

, so fraction

= \frac{2 \times \frac{4}{3} π r ^{3}}{( 4 r / 3 ) ^{3}} = \frac{3 π}{8} \approx 0.68

.

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