Differentiate between Boiling and Evaporation.

While both boiling and evaporation involve a liquid changing into a gas, they are distinct processes that occur under different conditions.

The Key Differences

Feature	Evaporation	Boiling
Type of Phenomenon	Surface Phenomenon: Only particles at the surface leave the liquid.	Bulk Phenomenon: Particles throughout the whole liquid change into vapor.
Temperature	Occurs at all temperatures below the boiling point.	Occurs only at a fixed temperature (the boiling point).
Speed	A slow and silent process.	A fast and rapid process.
Bubbles	No bubbles are formed within the liquid.	Bubbles form throughout the liquid and rise to the surface.
Cooling Effect	Always causes cooling of the surroundings.	Temperature of the liquid remains constant; no cooling effect.
Energy Source	Energy is taken from the liquid itself or the surroundings.	An external source of heat is usually required.

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Visualizing the Process

In evaporation, only the "fast-moving" particles at the top have enough energy to break away. In boiling, the heat is so intense that even the particles at the very bottom gain enough energy to form gas bubbles, which then fight their way up through the liquid.

Real-World Comparison

• Evaporation: Wet clothes drying under a fan or the sun. The water doesn't reach 100°C, yet it disappears over time.

• Boiling: Water bubbling in a kettle on a stove. This only happens once the water reaches its specific boiling threshold.