Rutherford's Gold Foil Experiment proved the presence of protons in the atom by observing the deflection of alpha particles.
Rutherford's Gold Foil Experiment:
Rutherford conducted the Gold Foil Experiment to test Thomson's plum pudding model of the atom. By bombarding a thin gold foil with alpha particles, he observed that while most particles passed through, some were deflected at large angles. This led to the proposal of the atom having a small, dense, positively charged nucleus at its center, providing evidence for the presence of protons in the atom.
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