Question
If three elements $A,\ B$ and $C$ crystallise in a cubic solid lattice with $A$ atoms at the corners, $B$ atoms at the cube centres and $C$ atoms at the centre of the faces of the cube, then write the formula of the compound.
✓
Answer
Atoms of $A$ per unit cell $=8\times\frac{1}{8}=1$
Atoms of $B$ per unit cell $= 1$
Atoms of $C$ per unit cell $=6\times\frac{1}{2}=3$
Hence, the formula is $ABC_3.$
Atoms of $B$ per unit cell $= 1$
Atoms of $C$ per unit cell $=6\times\frac{1}{2}=3$
Hence, the formula is $ABC_3.$
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