In Rutherford's scattering experiment of `alpha`-particles by metallic foils, with the increase of atomic number of nucleus, the scattering angle .

Options

A. Remains uncharged
B. Decreases
C. Increases
D. None of these

Answer

To solve the question regarding Rutherford's scattering experiment of alpha particles by metallic foils and the effect of increasing atomic number on the scattering angle, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Rutherford's Experiment**:
- Rutherford conducted experiments using alpha particles directed at a thin foil of gold. The scattering of these particles provided insights into the structure of the atom.

2. **Identify the Role of Atomic Number**:
- The atomic number (Z) of a nucleus indicates the number of protons it contains. A higher atomic number means a larger positive charge in the nucleus.

3. **Consider the Effect of Increased Charge**:
- As the atomic number increases, the positive charge of the nucleus increases. This leads to a stronger electrostatic repulsion between the positively charged alpha particles and the nucleus.

4. **Relate Charge to Scattering Angle**:
- The scattering angle is influenced by the strength of the repulsive force. A stronger repulsive force results in a larger deflection of the alpha particles, which means a larger scattering angle.

5. **Conclusion**:
- Therefore, with an increase in the atomic number of the nucleus, the scattering angle of the alpha particles also increases due to the increased repulsive force acting on them.

### Final Answer:
With the increase of atomic number of the nucleus, the scattering angle of alpha particles increases.

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