The laws of gases were developed in the late 18th century, when scientists began to realize that relationships between the pressure, volume, and temperature of a gas sample can be obtained that correspond to the approximation for all gases. where „V“ is the volume of a gas, „T“ is the absolute temperature, and k2 is a proportionality constant (which is not the same as the proportionality constants in the other equations in this article). Avogadro`s law (hypothetical in 1811) states that the volume absorbed by an ideal gas is directly proportional to the number of molecules of the gas present in the container. This results in a molar volume of a gas of about 22.4 l at STP (273.15 K, 1 atm). The relationship is given by These equations are only accurate for an ideal gas that neglects various intermolecular effects (see real gas). However, the ideal gas law is a good approximation for most gases under moderate pressure and temperature. As a mathematical equation, the Gay-Lussac law is written as follows: Charles` law, or the law of volumes, was found in 1787 by Jacques Charles. It states that for a given mass of an ideal gas at constant pressure, the volume is directly proportional to its absolute temperature, supplied in a closed system. The statement of Karl`s law is as follows: The volume (V) of a given mass of a gas at constant pressure (P) is directly proportional to its temperature (T). As a mathematical equation, Charles` law is written as follows: With the addition of Avogadro`s law, the law of combined gas develops into the law of ideal gas: the law of combined gas or the general equation of gas is obtained by combining Boyle`s law, Charles` law and Gay-Lussac`s law.

It shows the relationship between pressure, volume and temperature for a solid mass (quantity) of gas: In 1662, Robert Boyle studied the relationship between the volume and pressure of a gas in a fixed quantity at a constant temperature. He observed that the volume of a given mass of a gas is inversely proportional to its pressure at constant temperature. Boyle`s law, published in 1662, states that at a constant temperature, the product of the pressure and volume of a given mass of an ideal gas in a closed system is always constant. It can be verified experimentally with a pressure gauge and a variable volume container. It can also be derived from the kinetic theory of gases: when a container with a fixed number of molecules inside is reduced in volume, more molecules per unit of time hit a certain area on the sides of the container, resulting in higher pressure. The Gay Lussac Act, the Amontons Act or the Pressure Act were found in 1808 by Joseph Louis Gay-Lussac. He specifies that for a given mass and a constant volume of an ideal gas, the pressure exerted on the sides of its container is directly proportional to its absolute temperature. The concept can be represented with these formulas:. . .