Gas dioxide, and air expand to the same extent over the same 80 kelvin interval. He noted that, for an ideal gas at constant pressure, the volume is directly proportional to its temperature: In 1802, Joseph Louis Gay-Lussac published results of similar, though more extensive experiments. Gay-Lussac credited Charles' earlier work by naming the law in his honor. Gay-Lussac himself is credited with the law describing pressure, which he found in 1809. It states that the pressure exerted on a container's sides by an ideal gas is proportional to its temperature. In 1811, Amedeo Avogadro verified that equal volumes of pure
Gas (or molecules) present in the container. This gives rise to the molar volume of a gas, which at STP is 22.4 dm (or litres). The relation is given by where n is equal to the number of moles of gas (the number of molecules divided by Avogadro's Number). In 1801, John Dalton published the Law of Partial Pressures from his work with ideal gas law relationship: The pressure of a mixture of non reactive gases is equal to the sum of the pressures of all of the constituent gases alone. Mathematically, this can be represented for "n" species as: The