What does NOT affect the rate of evaporation of a liquid

Analyze the question: We need the one factor that does NOT affect how fast a liquid evaporates.

Concept: Evaporation is the escape of the fastest-moving molecules from the surface of a liquid at any temperature. Its rate depends on:

1. Surface area exposed: a larger area means more molecules can escape at once (so A affects it).
2. Humidity of the surroundings: if the air is already full of vapour, molecules return to the liquid more easily and the net evaporation is slower (so B affects it).
3. Nature of the liquid: volatile liquids like ether or alcohol evaporate faster than water because their intermolecular forces are weaker (so C affects it).
4. Temperature: higher temperature gives molecules more kinetic energy, so more can escape (so D affects it).
5. Other factors: air movement (wind) and pressure.

Check the last option:

• Volume of the liquid: evaporation happens at the surface, so the rate depends on the surface area, not on how much liquid is below it. A small puddle and a large pond with the same surface area and conditions have the same rate of evaporation per unit area. Volume does not affect the rate.

Answer: The factor that does not affect the rate is the volume of the liquid, which is option E.

Tip: Remember "evaporation is a surface phenomenon." If a factor doesn't change the surface, the energy of the molecules, or the vapour already in the air, it likely doesn't matter. Volume only tells you how long evaporation will take to finish, not how fast it happens.