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In a unit cell, atoms `(A)` are present at all corner lattices, `(B)` are present at alternate faces and all edge centres. Atoms `(C)` are present at face centres left from `(B)` and one at each body diagonal at disntance of `1//4th` of body diagonal from corner. Formula of given solid isA. `A_(3)B_(8)C_(7)`B. `AB_(4)C_(6)`C. `A_(6)B_(4)C_(8)`D. `A_(2)B_(9)C_(11)` |
Answer» Correct Answer - B Number of A atom `= 8("corner") xx 1/8 ("per corner share")` `= 1` Number of B atom `= 2("Alternate face") xx 1/2 ("face center share ")+12("edge")` `xx 1/4 ("edge centre share")` `= 1 + 3 = 4` Number of `C` atom `= 4 ("face centres of left from B")` `xx 1/2 ("face centre share")` `+1 ("at body diagonal")` `xx 4 ("body diagonal")` `= 2 + 4 = 6` Formula : `AB_(4) C_(6)`. |
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