Concept:Vapour pressure of a liquid rises when its temperature rises.
Explanation:When temperature increases, liquid molecules receive more kinetic energy.
More molecules gain enough energy to escape from the liquid surface into the vapour phase.
This increases the number of vapour molecules above the liquid.
As a result, the vapour pressure of the liquid increases.
Dissolving a salt in the liquid actually lowers its vapour pressure.
Increasing the volume of the liquid does not change its vapour pressure.
Lowering the temperature reduces the kinetic energy and decreases vapour pressure.
Therefore, the vapour pressure increases only when the temperature of the liquid rises.
Answer:D. temperature of the liquid rises