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(A) most of the mass of the atom is conc...

(A) most of the mass of the atom is concentrated in its nucleus.
(R) all alpha particles striking a gold sheet are scattered in different directions.

A

if both assertion and reason are true and reason is the correct explanation of assertion.

B

if both assertion and reason are true but reason is not the correct explanation of assertion.

C

if assertion is true but reason is false.

D

if both assertion and reason are false.

Text Solution

Verified by Experts

The correct Answer is:
C
The results of `alpha`- particle scattering experiment showed that most of the mass of the atom is concentrated in its nucleus. Not all but only high envery `alpha`-particles are scattered when thet strike an extremely thin foil of metal of passing through nucleus.
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