Avogadro's law "P" are taken at standard conditions for temperature and pressure (STP), then "k"'=1/"n", where "n" is Loschmidt constant. Avogadro's hypothesis (as it was known originally) was formulated in the same spirit of earlier empirical gas laws like Boyle's law (1662), Charles's law (1787) and Gay-Lussac's law (1808). The hypothesis was first published by Amadeo Avogadro in 1811, and reconciled Dalton atomic theory with the "incompatible" idea of Joseph Louis Gay-Lussac that some gases were composite of different fundamental substances (molecules) in integer proportions. In 1814, independently from Avogadro, André-Marie Ampère published the same law with similar conclusions. As Ampère was
Base conditions and temperature in which all 'net' volumes will be expressed. The density of a gas at a specific pressure can be estimated by using the ideal gas law. Doubling absolute pressure doubles the density of a gas, and doubling absolute temperature halves the density. The number of molecules in a given gas volume depends on the pressure and temperature. This is why the pressure and temperature must be stated in order for a volume measurement to mean anything. Density correction is also performed on liquids under measurement. For instance, the sticker on gasoline pumps that states that the volume is