Question

The co-ordination number of a chlorine ion in a sodium chloride lattice is _______.

• A. 6
• B. 8
• C. 5
• D. 4

Answer 1

The correct option is A 6

The number of oppositely charged ions surrounding an ion is called it's co-ordination number. In a sodium chloride crystal, each ${\text{Na}}^{+}$ is surrounded by six ${\text{Cl}}^{-}$ ions and each ${\text{Cl}}^{-}$ by six ${\text{Na}}^{+}$. So, the co-ordination number of chlorine in a sodium chloride lattice is 6.