What is the Molar Volume of a Gas at STP? The Mole and the Volume of GasIt is rather tricky to find the number of moles of a gas by weighing its mass. Chemists determine the number of moles of any gas by measuring its volume. However, this cannot be done for solids and liquids. It is found that under the same temperature and pressure, equal volumes of all gases … [Read more...] about What is the Molar Volume of a Gas at STP?