Correct Answer: volume of gases

Solution : The correct option is the volume of gases .

The volume of a gas mixture changes after a physical or chemical change, and a eudiometer is a laboratory instrument that monitors this change. It typically comes in two sizes, 50 mL and 100 mL, and in general, it resembles a graduated cylinder. The bottom end is submerged in water or mercury, while the top end is closed. In the cylinder, the liquid catches a sample of gas, and the graduation makes it possible to calculate the volume of the gas.