Avogadro's law

(Chemistry) principle which states that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules

Avogadro's law (Avogadro's Hypothesis, or Avogadro's Principle) is a gas law named after Amedeo Avogadro, who in 1811 hypothesized that:Equal volumes of gases, at the same temperature and pressure, contain the same number of particles, or molecules.Thus, the number of molecules in a specific volume of gas is independent of the size or mass of the gas molecules. As an example, equal volumes of molecular hydrogen and nitrogen would contain the same number of molecules, as long as they are at the same temperature and pressure.The minor aspect of the law can be stated mathematically as:.
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Noun
1. the principle that equal volumes of all gases (given the same temperature and pressure) contain equal numbers of molecules
(synonym) Avogadro's hypothesis
(hypernym) law, law of nature

Equal volumes of an ideal gas contain equal numbers of molecules, if both volumes are at the same temperature and pressure. For example, 1 L of ideal gas contains twice as many molecules as 0.5 L of ideal gas at the same temperature and pressure.

LEGGE DI AVOGADRO