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JEE Main levelSingle correct optionDifficulty 2 of 3ss118

For the same atomic radius, the ratio of the unit cell edge of an fcc metal to that of a bcc metal is

A0.82
B1.41
C1.22
D1.15

Answer: C

fcc:

a = 22 r

. bcc:

a = 4 r / 3

. Ratio

= \frac{2 2 3}{4} = \frac{6}{2} = 1.225 \approx 1.22

.

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