A. True. Vapor pressure is the pressure exerted by all of the air molecules within a specific environment because the molecules are constantly in motion and exert a pressure on the walls of the container they are in. This pressure is known as vapor pressure. The vapor pressure of a gas is determined by the temperature of the gas and the number of molecules present. As the temperature increases, the molecules move faster and exert more pressure, and as the number of molecules increases, the pressure increases as well.
