In a `f.c.c.` arrangement of `A` and `B` atoms, where `A` atoms are at the corners of the unit cell and `B` atoms at the face `-` centres, one of the `A` atom is missing from one corner in each unit cell. The formula of compound is `:`A. `A_(24)B_(7)`B. `A_(7)B_(24)`C. `A_(7)B_(28)`D. `A_(28)B_(7)`

In a `f.c.c.` arrangement of `A` and `B` atoms, where `A` atoms are at

1.	In a `f.c.c.` arrangement of `A` and `B` atoms, where `A` atoms are at the corners of the unit cell and `B` atoms at the face `-` centres, one of the `A` atom is missing from one corner in each unit cell. The formula of compound is `:`A. `A_(24)B_(7)`B. `A_(7)B_(24)`C. `A_(7)B_(28)`D. `A_(28)B_(7)`
Answer» Correct Answer - b No. of atom `A` from the corner of unit cell `=(7)/(8)` No. of atom `B` from the face of unit cell `=3` Thus `A:B::(7)/(8):(3)/(1)` or `A:B::7:24` `:.` Formula is `A_(7)B_(24)`

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In a `f.c.c.` arrangement of `A` and `B` atoms, where `A` atoms are at the corners of the unit cell and `B` atoms at the face `-` centres, one of the `A` atom is missing from one corner in each unit cell. The formula of compound is `:`A. `A_(24)B_(7)`B. `A_(7)B_(24)`C. `A_(7)B_(28)`D. `A_(28)B_(7)`

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