Concept:Evaporation is strictly a surface phenomenon. The rate at which molecules escape from the liquid phase into the gas phase is directly proportional to the exposed surface area of the liquid.
Formula:$$ \text{Rate of Evaporation} \propto \text{Surface Area} $$
Solution:- A saucepan has a broad, flat design, providing a significantly larger exposed surface area compared to a cup, glass, or small bowl.
- Because more surface water molecules are exposed to the air and can absorb ambient thermal energy, more molecules can reach escape velocity simultaneously.
- Thus, water will evaporate the fastest (earliest) from the saucepan.
Why other options are incorrect:Cups and glasses are typically tall and narrow, limiting the surface area and drastically slowing down the evaporation rate.
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