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One of the allotropic form of boron is a...

One of the allotropic form of boron is `alpha -` rhombohedral boron. Number of faces and corners in its basic building `B_(12)` icosahedral unit are:

A

20 and 12 respectively

B

12 and 20 respectively

C

12 and 12 respectively

D

20 and 20 respectively

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Verified by Experts

The correct Answer is:
A
`B_(12) = 12` corners
Icosahedral `=20` faces.
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