Question

Rutherford’s α–particle scattering experiment showed that

(i) electrons have a negative charge

(ii) the mass and positive charge of the atom are concentrated in the nucleus

(iii) neutron exists in the nucleus

(iv) most of the space in an atom is empty. Which of the above statements are correct?

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

Answer 1

The correct option is B

(ii) and (iv)

Explanation for correct option:

Option B

Rutherford's model of an atom:

• The whole mass and positive charge of an atom are concentrated in a very small region at the center, known as the nucleus.
• The positive charge on the nucleus is due to protons. The number of protons is different for atoms of different elements, therefore, the magnitude of positive charge on the nucleus is different for atoms of different elements.
• The nucleus is surrounded by negatively charged particles called electrons.
• The number of electrons in an atom is equal to the number of protons (positively charged) in the nucleus.
• Thus, the atom as a whole is neutral.
• Most of the space in an atom is empty.

Therefore, option B is correct.