Rutherford's `alpha`-particle scattering experiment showed that
(i) electrons have negative charge.
(ii) the mass and positive charge of the atom is concentrated in the nucleus.
(iii) neutron exists in the nucleus.
(iv) most of the space in atom is empty.
Which of the above statements are correct ?

Options

A. (i) and (iii)
B. (ii) and (iv)
C. (i) and (iv)
D. (iii) and (iv)

Explanation

To determine which statements regarding Rutherford's alpha-particle scattering experiment are correct, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement (i): Electrons have negative charge.**
- This statement is true, but it is important to note that the discovery of the negative charge of electrons was made by J.J. Thomson through his plum pudding model, not by Rutherford. Therefore, this statement is **incorrect** in the context of Rutherford's experiment.

2. **Statement (ii): The mass and positive charge of the atom is concentrated in the nucleus.**
- This statement is correct. Rutherford's experiment concluded that the atom has a small, dense nucleus that contains most of its mass and positive charge. Thus, this statement is **correct**.

3. **Statement (iii): Neutron exists in the nucleus.**
- While it is true that neutrons exist in the nucleus, this discovery was made by James Chadwick, not Rutherford. Rutherford's experiment did not provide evidence for the existence of neutrons. Therefore, this statement is **incorrect** in the context of Rutherford's findings.

4. **Statement (iv): Most of the space in the atom is empty.**
- This statement is also correct. Rutherford observed that most alpha particles passed through the gold foil without any deflection, indicating that atoms are mostly empty space. Thus, this statement is **correct**.

### Conclusion:
Based on the analysis:
- The correct statements according to Rutherford's alpha-particle scattering experiment are:
- (ii) The mass and positive charge of the atom is concentrated in the nucleus.
- (iv) Most of the space in the atom is empty.

Therefore, the correct answer is that statements **(ii) and (iv) are correct**.