In ${\mathrm{PO}}_4^{3-}$ ion, the formal charge on the oxygen atom of the P-O bond is : 

In ${\mathrm{NO}}_3^{-}$ ion, the number of bond pairs and lone pairs of electrons exhibited by nitrogen atom is:

1. 2, 2

2. 3, 1

3. 1, 3

4. 4, 0

An isoelectronic pair among the following is:

(a) Na⁺, Mg²⁺ 

(b) Al³⁺, O^– 

(c) Na⁺, O^2– 

(d) N^3-, Cl^– 

Which of the following attain the linear structure?

(a) ${\mathrm{BeCl}}_2$

(b) ${\mathrm{NCO}}^{+}$

(c) ${\mathrm{NO}}_2$

(d) ${\mathrm{CS}}_2$

Choose the correct option

CO is isoelectronic with

(a) ${\mathrm{NO}}^{+}$

(b) ${\mathrm{N}}_2$

(c) ${\mathrm{SnCl}}_2$

(d) ${\mathrm{NO}}_2^{-}$

Choose the correct option

1. (a), (b)

2. (b), (c)

3. (c), (d)

4. (b), (d)

Among the following, the correct statements about ${\mathrm{CO}}_3^{2- }$

Choose the correct option :

Which of the following is isoelectronic pair?

Which of the following pairs of ions are isoelectronic and isostructural?
\(a. \mathrm{CO}_{3}^{2-}, \mathrm{NO}_{3}^{-} \\ b. \mathrm{ClO}_{3}^{-}, \mathrm{CO}_{3}^{2-} \\ c. \mathrm{SO}_{3}^{2-}, \mathrm{NO}_{3}^{-} \\ d. \mathrm{ClO}_{3}^{-}, \mathrm{SO}_{3}^{2-} \\\)