What is molar volume? The volume occupied by 1 mole of any substance at a given temperature and pressure. The volume of gas at high pressure and low temperature. The volume occupied by 1 mole of a gas at standard temperature and pressure (STP). The volume of gas needed to react with 1 mole of another substance.

The correct answer is: The volume occupied by 1 mole of a gas at standard temperature and pressure (STP).<br /><br />Molar volume is the volume occupied by one mole of a substance, typically a gas, at a specific temperature and pressure. At standard temperature and pressure (STP), which is defined as a temperature of 0°C (273.15 K) and a pressure of 1 atm (101.325 kPa), the molar volume of an ideal gas is approximately 22.414 liters. This value is often used as a reference for calculating the molar volume of gases under different conditions using the ideal gas law.