Question

Which describes Ernest Rutherford’s experiment?

A)Positive particles are fired at gold foil. Most bounce back, but some pass through.

B)Negative particles are fired at gold foil. Most bounce back, but some pass through.

C)Positive particles are fired at gold foil. Most pass through, but some bounce back.

D)Negative particles are fired at gold foil. Most pass through, but some bounce back.

Answer 1

Answer: The correct option is C.

Explanation: Ernest Rutherford proposed a gold-foil experiment.

In his experiment, he took a Gold foil & fired
`\alpha` - particles (carrying +4 charge). He, then put a photogenic film around the gold foil to have a look where the particles are going. He thought that the alpha-particles will pass through the gold-foil because it was very thin.

But to his surprise he observed that some particles bounced back. This observation will either mean that the alpha-particles are hitting something hard or hitting something that carries positive charge because positive charges repel each other.

Therefore, he made proposed that the nucleus is carrying some positive charge that consists of protons.

Hence, the correct option is C.

Answer 2

Answer : Option C) Positive particles are fired at gold foil. Most pass through, but some bounce back.

Explanation : In Ernest Rutherford's experiment he used a beam of alpha particles which were aimed at very thin gold foil and their passage through the foil was detected. Now, these alpha particles were the positive particles which were fired on the gold foil. Many of the alpha particles were found to pass through the foil but there were some particles which bounced back. This whole model was called as plum pudding model for his study.