Question

Rutherford's alpha particle scattering experiment established that:

• A. Positive charge is not evenly distributed throughout an atom
• B. Electrons are negatively charged
• C. Electrons are positively charged
• D. Atoms are made up of protons, neutrons and electrons

Answer 1

The correct option is A Positive charge is not evenly distributed throughout an atom

Rutherford bombarded a thin sheet of gold with alpha particles in an evacuated chamber. He made the following observations:

$\bullet$ Most of the alpha particles passed straight through the foil without any deflection from the path.
$\bullet$ A small fraction of them was deflected from their original path by small angles, only a few particles bounced back.

From these observations, he arrived at the following conclusions:
$\bullet$ Positive charge is present at the centre of an atom in a very small space.
$\bullet$ Most of the space in an atom is empty.
$\bullet$ Entire mass of an atom is concentrated at the centre. Hence, he proved that the positive charge is not distributed in an even manner inside the atom.