A solid (A) reacts with strong aqueous NaOH, liberating a foul smelling gas (B), which spontaneously burns in the air, giving smoky rings. A and B are, respectively:
1. P4 (red) and PH3
2. P4 (white) and PH3
3. S8 and H2S
4. P4 (white) and H2S
Which of the following gases is the easiest to liquefy?
1. | Ar | 2. | Ne |
3. | Xe | 4. | Kr |
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.
2.
3.
4.
An element belongs to group 15 and 3rd 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?
1. | Xe is the most reactive among the rare gases. |
2. | He is an inert gas. |
3. | Radon is obtained from the decay of radium. |
4. | The most abundant rare gas found in the atmosphere is He. |
The strongest reducing agent is:
1.
2.
3.
4.
A compound among the following that has an -O-O- linkage is:
1.
2.
3.
4.
The respective oxidation states of P in H4P2O5, H4P2O6, and H4P2O7 are:
1. | +3, +5, and +4 | 2. | +5, +3, and +4 |
3. | +5, +4, and +3 | 4. | +3, +4, and +5 |
A balanced chemical equation for the reaction showing catalytic oxidation of NH3 by atmospheric oxygen is:
1. | 4NH3 + \(\underset{\text{From air}}{5O_2} \) \(\xrightarrow[\text{500 K; 9 bar}]{\text{Pt / Rh gauge catalyst}}\) 4NO + 6H2O |
2. | 3NH4 + \(\underset{\text{From air}}{5O_2} \) \(\xrightarrow[\text{500 K; 9 bar}]{\text{Pt / Rh gauge catalyst}}\) 3NO + 6H2O |
3. | 4NH3 + \(\underset{\text{From air}}{5O_2} \) \(\xrightarrow[\text{cold}]{\text{no catalyst}}\) 4NO + 6H2O |
4. | 3NH4 + \(\underset{\text{From air}}{5O_2} \) \(\xrightarrow[\text{cold}]{\text{no catalyst}}\) 3NO + 6H2O |