What is the co-ordination number of sodium in `Na_(2)O` ?

Options

A. 6
B. 4
C. 8
D. 2

Answer

B

Explanation

In `Na_(2)O`, each oxide ions `(O^(2-))` is co-ordinated to `8 Na^(+)` ions and each `Na^(+)` ion to 4 oxide ions. Hence if has 4:8 co-ordination.