How was the structure of the atom discovered

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Explanation:

Building on the Curies' work, the British physicist Ernest Rutherford (1871–1937) performed decisive experiments that led to the modern view of the structure of the atom. ... Because it was the first kind of radiation to be discovered, Rutherford called these substances α particles.

c is the answer because when something is left after something evaporates that shows the chemical change.

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