When the surface area exposed is more, the molecules get greater opportunity to escape. Hence more molecules escape and rate of evaporation increases.

Lesson Summary This is followed by condensation, which is the process by which water vapor is changed back into liquid water. Then, water becomes precipitation, which is water falling from the clouds as rain, freezing rain, sleet, snow, or hail.

So what would happen if there were no condensation stage? The condensation stage is the one where water vapour gathers together into clouds (and when the clouds become heavy enough with vapour, release water as rain). So the first answer is that there would be no clouds.

As the temperature of a liquid or solid increases its vapor pressure also increases. Conversely, vapor pressure decreases as the temperature decreases.

When a non-volatile solute that is salt is added to a solvent that water, the vapour pressure of the resulting solution (salt solution) is less than the vapour pressure above the pure solvent (water). Thus rate of evaporation decreases. Hence, rate of evaporation decreases.

Results show that the evaporation rate decreases as NaCl concentration increases only up to a certain level. When exceeding this level, any further increase of NaCl concentration results in higher evaporation rates which is described theoretically using the thermodynamics of the solution.

The results show a decrease in the evaporation rate with an increase of the water salinity because of the reduction in the water vapor pressure at the water surface.

You can think of it this way: Dissolving the salt requires energy, so the evaporation temperature increases with the amount of salt added (you need to add more energy to get the water to “boil”).