Knowledge database: Basic laws of chemistry: Ideal gas law

The ideal gas law states the interdependence of pressure, tempreature, amount of substance, and the volume of a gas. It was obtained by combining Boyle-Mariotte's law, Charles-Gay-Lussac's law and Avogadro's law, and can be expressed by the formula p*V = R*n*T, where p is the pressure, V the volume, n is the amount of gas, T is the thermodynamic temperature, and R is the universal gas constant, which equals 8.3143 Pa m³ K^-1 mol^-1.

The ideal gas law is valid, as the name itself suggests, in cases in which we deal with ideal gases. In case of ideal gases, we assume that the distances between the particles of such gases are very large, and therefore the bonds between the particles are very weak.

To some extent, the ideal gas law can be applied to real gases, provided that they do not differ too much from the mentioned ideal gas conditions. By having a too high pressure and a too low temperature, the distance between the particles of gas are reduced and the forces between them become stronger. In such cases, more complex formulas need to be applied.