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Question
State two observations which show that atom is not indivisible.
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Solution
Two observations, which show that an atom is divisible are-
(1) Discharge-tube experiment : In J. J. Thomson's experiment, the stream of cathode rays in the gas-discharge tube shows the presence of negatively charged subatomic particles called electrons.
(2) In Goldstein's experiment, the faint red glow in the gas discharge tube shows the presence of positively charged subatomic particles called protons.
These experiments show that atoms are divisible and made up of subatomic particles, electrons, protons and neutrons.
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