What is the volume of one mole of gas at room temperature and pressure (RTP)?

One mole of gas at room temperature and pressure (RTP) occupies a volume of 24 litres.

At room temperature and pressure (RTP), which is defined as a temperature of 20 degrees Celsius and a pressure of 1 atmosphere, one mole of any gas occupies a volume of 24 litres. This is known as the molar volume of a gas at RTP.

The concept of molar volume is based on Avogadro's law, which states that equal volumes of all gases, at the same temperature and pressure, contain an equal number of molecules. This means that whether you have a mole of oxygen, nitrogen, or any other gas, at RTP it will occupy a volume of 24 litres.

The molar volume is a very useful concept in chemistry, particularly in stoichiometry, the study of the quantitative relationships between reactants and products in a chemical reaction. For example, if you know the volume of a gas at RTP, you can easily calculate the number of moles, and vice versa.

Remember, the molar volume of 24 litres per mole at RTP is an average value. Real gases may deviate slightly from this value due to interactions between gas molecules. However, for most practical purposes in IGCSE Chemistry, you can use the molar volume of 24 litres per mole at RTP as a reliable approximation.