Which of the following compounds is not an acidic salt?

1. NaH₂PO₂

2. NaH₂PO₃

3. Na₂H₂S₂O₇

4. NaH₂PO₄

Hydrogen peroxide can be generated by the hydrolysis of

1. ${\mathrm{HNO}}_3$

2. ${\mathrm{H}}_2{\mathrm{P}}_2\mathrm{O}$

3. ${\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_8$

4. ${\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_6$

The strongest reducing agent is:

1. $H_4{P}_2{O}_7$

2. $H_{3}P{O}_3$

3. $H_{3}P{O}_2$

4. $H_{3}P{O}_4$

A compound among the following that has an -O-O- linkage is:

1. ${\mathrm{H}}_2{\mathrm{SO}}_4$$,$ $\mathrm{sulphuric}$ $\mathrm{acid}$

2. ${\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_8,$ $\mathrm{peroxodisulphuric}$ $\mathrm{acid}$

3. ${\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_7,$ $\mathrm{pyrosulphuric}$ $\mathrm{acid}$

4. ${\mathrm{H}}_2{\mathrm{SO}}_3,$ $\mathrm{sulphurous}$ $\mathrm{acid}$

Which of the following gases is the easiest to liquefy?

An element belongs to group 15 and 3^rd period of the periodic table. Its electronic configuration would be:
1. \(\mathrm{1 s^2 2 s^2 2 p^4} \)
2. \(\mathrm{1 s^2 2 s^2 2 p^3} \)
3. \(\mathrm{1 s^2 2 s^2 2 p^6 3 s^2 3 p^2} \)
4. \(\mathrm{1 s^2 2 s^2 2 p^6 3 s^2 3 p^3}\)

Which of the following statements is false? 

A balanced chemical equation for the reaction showing catalytic oxidation of NH₃ by atmospheric oxygen is:

The correct structure of pyrophosphoric acid is:

1.		2.
3.		4.

PH₃ forms bubbles when passed slowly through water but NH₃ gets dissolved in water, because: