Chemistry
Explain in brief - Goldstein's experiment which led to the discovery of the proton and - Lord Rutherford's experiment which led to the discovery of the atomic nucleus.
Answer
Goldstein's Experiment:
Goldstein used a modified cathode ray tube with a perforated cathode and observed new type of rays produced from the anode passing through the hole of the perforated cathode. These rays were called - Anode rays.
The positive rays were affected by electric & magnetic fields but in a direction opposite to that of cathode rays.
Goldstein concluded that anode rays or positive rays consist of positively charged particles called protons.
Lord Rutherford's Experiment:
Lord Rutherford projected alpha particles towards a thin gold foil in the path of the rays.
He observed that most of the alpha particles went straight through the foil but some were deflected slightly & some by large angles.
He concluded that an atom on the whole is relatively empty but consists of a concentrated positive mass in the centre which lead to the deflection of the alpha particles. Hence, Lord Rutherford discovered atomic nucleus.
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