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Q.
Coordination number of $Cs ^{+}$ and $Cl ^{-}$ in $CsCl$ crystal are:
The Solid State
Solution:
Each Cs ion is surrounded by $8 Cl ^{-}$ ions and each $Cl ^{-}$ ion is surrounded by $8 Cs ^{+}$ ions. $CsCl$ has a bcc type structure in which $Cs ^{+}$ occupy the centre of cube. Thus, the structure has $8: 8 $ coordination number.