The ideal gas law can also be written and solved in terms of the number of moles of gas: p V = n R T , where n is the number of moles and R is the universal gas constant, R = 8.31 J/mol · K The ideal gas law relates the pressure and volume of a gas to the number of gas molecules and the temperature of the gas

The number of molecules in a mole is called Avogadro’s number N A , N A = 6.02 × 10 23 mol -1 The van der Waals equation of state for gases is valid closer to the boiling point than the ideal gas law

kinetic theory of gases — theory that derives the macroscopic properties of gases from the motion of the molecules they consist of. mole — quantity of a substance whose mass (in grams) is equal to its molecular mass. ideal gas law — physical law that relates the pressure and volume of a gas, far from liquefaction, to the number of gas molecules or number of moles of gas and the temperature of the gas. supercritical — condition of a fluid being at such a high temperature and pressure that the liquid phase cannot exist.