Question

The total number of valence electrons in 4.2 gm of ${N_3}^{-}$ ion is ($N_A$ is the Avogadro's number )

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

42 g of ${N_3}^{-}$ ions have 16 $N_A$ valence electrons

4.2g of ${N_3}^{-}$ ions have = $\frac{16N_A}{42}$ $\times$ 4.2 = 1.6 $N_A$