John Dalton defined an atom as a small indivisible particle that cannot be created or destroyed. (1 jan 1808 ano – 23 h 59 m, 31 dez 1808 ano)

Descrição:

It is believed that this model could have been derived from lawn bowling balls (a recreational hobby of Dalton's). It's supported by the Law of Definite Proportions (atoms in compounds always join in the same ratio), the Law of Multiple Proportions (the masses of elements in compounds also join in ratios), and the Law of Conservation of Mass (mass cannot be created nor destroyed).

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