Question

A sample of octane in equilibrium with its vapor in a closed 1.0 L container has a vapor pressure of 50 torr at 45oC. The container’s volume is increased to 2.0 L at constant temperature and equilibrium is re-established. What is the vapor pressure?

The answer I got was 25 torr, but the correct answer is 50 torr. Why would the pressure not half when the volume is doubled?

Answer 1

vapor pressure is a characteristic of the equilibrium between a liquid and a vapor at a given temperature. It does not depend on volume.

The color of the sky is blue, it does not matter how much of the sky one sees.