What happens to the position of an element in the periodic table when its nucleus emits (a) an `alpha`-particle, (b) a `beta`-particle and (c ) `gamma` radiation ? Give reason for your answer.

Answer

To determine how the position of an element in the periodic table changes when its nucleus emits different types of radiation, we will analyze the effects of alpha particles, beta particles, and gamma radiation on the atomic number of the element.

### Step-by-Step Solution:

1. **Alpha Particle Emission:**
- When an element emits an alpha particle, it loses 2 protons and 2 neutrons from its nucleus.
- This results in a decrease in the atomic number by 2 units.
- Since the atomic number determines the position of an element in the periodic table, a decrease by 2 means the element shifts to the left in the periodic table.

2. **Beta Particle Emission:**
- In beta decay, a neutron in the nucleus is converted into a proton, which results in the emission of a beta particle (an electron).
- This process increases the atomic number by 1 unit because a new proton is added to the nucleus.
- Therefore, the element shifts to the right in the periodic table due to this increase in atomic number.

3. **Gamma Radiation Emission:**
- Gamma radiation is a form of electromagnetic radiation and does not involve the emission of particles that change the number of protons or neutrons in the nucleus.
- As a result, the atomic number remains unchanged during gamma decay.
- Consequently, there is no shift in the position of the element in the periodic table.

### Summary of Changes:
- **Alpha Particle Emission:** Decreases atomic number by 2 → Shifts left in the periodic table.
- **Beta Particle Emission:** Increases atomic number by 1 → Shifts right in the periodic table.
- **Gamma Radiation:** Atomic number remains the same → No shift in the periodic table.