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Question
Assertion: Total number of octahedral voids present in unit cell of cubic close packing including the one that is present at the body centre, is four.
Reason: Besides the body centre there is one octahedral void present at the centre of each of the six faces of the unit cell and each of which is shared between two adjacent unit cells.
Options
Assertion and reason both are correct statements and reason is correct explanation for assertion.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Assertion is correct statement but reason is wrong statement.
Assertion is wrong statement but reason is correct statement.
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Solution
Assertion is correct statement but reason is wrong statement.
Explanation:
The correct statement for reason is,
"Besides the body centre there is one octahedral void at the centre of each 12 edges which is shared between four adjacent unit cells".
Thus, Octahedral voids present at the body centre of the cube = 1
12 ocahedral voids located at each edge and shared between four unit cells = `12 xx 1/4` = 3
Total number of octahedral voids = 4.
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