Which law states that the pressure and absolute temperature of a fixed quantity of gas are directly proportional under constant volume conditions?

Gay-Lussac's law, Amontons' law or the pressure law was found by Joseph Louis Gay-Lussac in 1809.

Explanation:

It states that, for a given mass and constant volume of an ideal gas, the pressure exerted on the sides of its container is directly proportional to its absolute temperature.

Gay-Lussac's law

Explanation:

Gay-Lussac's second law, which is called isochoric transformation or isovolumetric transformation, is related to the behavior of gases when subjected to a constant volume. The elaboration of this law was attended by the French scientist Jacques Alexandre Cesar Charles.

According to Lussac, when a gas is placed in a container at a constant volume, it is found that if a pressure is exerted on that gas, a proportional increase in the absolute temperature of that gas will occur.

Generally, under Gay-Lussac law, a gas's pressure and temperature will always be directly proportional as long as the volume is constant. Thus, increasing the pressure increases the temperature; decreasing the pressure decreases the temperature.