English chemist John Dalton read his first atomic theory paper to the Manchester Literary and Philosophical society.

Dalton’s paper was “On the Absorption of Gases by Water and other Liquids,” and it contained Dalton’s Law. It’s also known as Dalton’s law of partial pressures. It is used to prove that the total pressure from a mixture of non-reacting gases is the same as the partial pressures of the individual gases in the mixture, which means that the mixture doesn’t increase exerted pressure.

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