The mass number of a nucleus is equal to:
| 1. | the number of neutrons in the nucleus. |
| 2. | the number of protons in the nucleus. |
| 3. | the number of nucleons in the nucleus. |
| 4. | none of them. |
| (a) | \(\alpha\text-\)decay | (b) | \(\beta^{+}\text-\)decay |
| (c) | \(\beta^{-}\text{-}\)decay | (d) | \(\gamma\text-\)decay |
Choose the correct option:
| 1. | (a), (b) | 2. | (b), (c) |
| 3. | (c) | 4. | (a), (d) |
| 1. | is only attractive force. |
| 2. | is only repulsive force. |
| 3. | maybe attractive or repulsive in nature depending on the distance. |
| 4. | is a central force. |
| 1. | |
2. | |
| 3. | 4. |
| 1. | The conservation of charge |
| 2. | The conservation of mass |
| 3. | The conservation of mass energy |
| 4. | The conservation of momentum |
| 1. | \({ }_{12}^{22} \mathrm{Mg}\) | 2. | \({ }_{11}^{23} \mathrm{Na}\) |
| 3. | \({ }_{10}^{23} \mathrm{Ne}\) | 4. | \(_{10}^{22}\textrm{Ne}\) |
| Assertion (A): | In \(\alpha \text-\text{decay}\) atomic number of the daughter nucleus is reduced by \(2\) units from the parent nucleus. |
| Reason (R): | An \(\alpha \text-\text{particle}\) carries four units of mass. |
| 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. |