Final answer:
John Dalton formulated Dalton's atomic theory based on the hypothesis proposed by Greek philosophers Leucippus and Democritus in the 5th century BCE. His atomic theory explained the composition of matter and the behavior of atoms in chemical reactions.
Step-by-step explanation:
John Dalton formulated Dalton's atomic theory based on the hypothesis proposed by Greek philosophers Leucippus and Democritus in the 5th century BCE. Dalton, a British schoolteacher, supported the idea that matter is composed of atoms with quantitative measurements. His atomic theory explained that elements are made up of unique types of atoms that combine in fixed, small, whole-number ratios to form compounds. Additionally, Dalton's theory highlighted the concept that atoms are neither created nor destroyed during a chemical change.
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