# in a face centered cubic arrangement of A and B ,A are present at the corners of the unit cell and B are present at the face centeres.If one atom of A is missing from its position at the corner , what is the formula of the compound?

### Asked by vasturushi | 18th Jul, 2017, 12:06: PM

Expert Answer:

### Number of atoms of A from corners of unit cell = 7/8
Number of atoms of B from faces of unit cell = 3
Thus, A:B = 7/8 : 3 or 7 : 24
So, the formula is A_{7}B_{24}

_{7}B

_{24}

### Answered by Prachi Sawant | 18th Jul, 2017, 06:41: PM

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