Q. No.Why does nitrogen exist as N₂ while phosphorus exists as P₄?
1.
The tendency to form pπ–pπ bonds decreases on moving up the group.
2.
The tendency to form pπ–pπ bonds decreases on moving down the group.
3.
The tendency to form dπ–dπ bonds decreases on moving down the group.
4.
The tendency to form dπ–dπ bonds decreases on moving up the group.
A chemical that depletes the ozone layer is:
1. Sulphur
2. Chlorofluorocarbons (CFCs)
3. Nitrogen
4. Hydrogen
Which of the following correctly explains why oxygen can participate in hydrogen bonding whereas chlorine generally does not?
| 1. | Chlorine has a bigger size and as a result, a higher electron density per unit volume. |
| 2. | Oxygen has a smaller size and as a result, a lower electron density per unit volume. |
| 3. | Oxygen has a smaller size and as a result, a higher electron density per unit volume. |
| 4. | Oxygen has a bigger size and as a result, a higher electron density per unit volume. |
Which of the following explains why oxygen is a gas while sulphur is a solid?
1. Oxygen is less electronegative than sulphur.
2. Sulphur is smaller than the oxygen molecule.
3. Sulphur readily forms pπ–pπ bonds.
4. Oxygen tends to form pπ-pπ bonds.
| 1. | Neon gas is filled in discharge tubes with characteristic colours. |
| 2. | Neon gas is used in beacon lights. |
| 3. | Argon along with nitrogen is used in gas-filled electric lamps. |
| 4. | All of the above. |
Choose the incorrect statement among the following regarding noble gases:
| 1. | Noble gases have weak dispersion forces. |
| 2. | Noble gases have large positive values of electron gain enthalpy. |
| 3. | Noble gases are sparingly soluble in water. |
| 4. | Noble gases have very high melting and boiling points. |
Which of the following correctly explains why NH₃ forms hydrogen bonds whereas PH₃ does not?
| 1. | Phosphorus is more electronegative as compared to nitrogen. |
| 2. | Nitrogen is more electronegative as compared to phosphorus. |
| 3. | Nitrogen and phosphorous have equal electronegativity. |
| 4. | Nitrogen is more stable as compared to phosphorus. |
Which of the following oxyacids of phosphorus contains two direct P–H bonds?
1. \(\mathrm{H}_3 \mathrm{PO}_2\)
2. \(\mathrm{H}_3 \mathrm{PO}_3\)
3. \(\mathrm{H}_3 \mathrm{PO}_4\)
4. \(\mathrm{H}_4 \mathrm{P}_2 \mathrm{O}_7\)
| Assertion (A): | The valency and oxidation number of sulphur in S8 respectively are 2 and 0. |
| Reason (R): | S8 Rhombic is the most stable allotropic form of sulphur. |
| 1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
| 3. | (A) is true but (R) is false. |
| 4. | Both (A) and (R) are false. |
| Assertion (A): | Noble gases have the highest ionization energies in their respective periods. |
| Reason (R): | The outermost sub-shell of noble gases in which the electron enters is completely filled. |
Select the correct option based on statements below:
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A) |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A) |
| 3. | (A) is True but (R) is False |
| 4. | Both (A) and (R) are False |
© 2026 GoodEd Technologies Pvt. Ltd.