DALTON'S LAW

n. Dalton's law of partial pressure, physical law that says that the total pressure used by a gaseous mixture equals to the sum of the partial pressures of gases if they alone were present (Law named after the famous English physicist John Dalton)

In chemistry and physics, Dalton's law (also called Dalton's law of partial pressures) states that the total pressure exerted by a gaseous mixture is equal to the sum of the partial pressures of each individual component in a gas mixture. This empirical law was observed by John Dalton in 1801 and is related to the ideal gas laws.
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Noun
1. (chemistry) law stating that when two elements can combine to form more than one compound the amounts of one of them that combines with a fixed amount of the other will exhibit a simple multiple relation
(synonym) law of multiple proportions
(hypernym) law, law of nature
(classification) chemistry, chemical science
2. (chemistry and physics) law stating that the pressure exerted by a mixture of gases equals the sum of the partial pressures of the gases in the mixture; the pressure of a gas in a mixture equals the pressure it would exert if it occupied the same volume alone at the same temperature
(synonym) Dalton's law of partial pressures, law of partial pressures
(hypernym) law, law of nature
(classification) chemistry, chemical science

The total pressure exerted by a mixture of gases is the sum of the pressures that each gas would exert if it were alone. For example, if dry oxygen gas at 713 torr is saturated with water vapor at 25 torr, the pressure of the wet gas is 738 torr.