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Question
Explain in brief the experimental proof which led to the discovery of –
Electrons
Solution
Electrons: English physicist William Crookes in 1878 discovered the cathode rays
He found that when an electric discharge is passed through a tube containing a gas at low pressure (0.01 mm of Hg).
Blue rays were emitted from the negative plate [i.e. cathode]. These rays were called cathode rays and consist of negatively charged particles now called electrons. Electrons are an essential part of each and every atom.
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