Question

Define Boiling Point, Melting Point and Evaporation.

Answer 1

Step 1: Definition of boiling point.

• Boiling point of any substance is defined as the temperature at which the liquid phase of that substance converts into its vapor phase at atmospheric pressure.
• Example, boiling point of Water $\left({\mathrm{H}}_2\mathrm{O}\right)$ is $100°\mathrm{C}$.

Step 2: Definition of melting point.

• Melting point of any substance is defined as the temperature at which the solid phase of that substance converts into its liquid phase at atmospheric pressure.
• Example, melting point of Water $\left({\mathrm{H}}_2\mathrm{O}\right)$ is $0°\mathrm{C}$.

Step 3: Definition of evaporation.

• Evaporation of any substance is the process in which the liquid phase of that substance converts into its vapor phase at a temperature lower than its boiling point.
• Liquid molecules at the surface collide with each other and attain sufficient amount of kinetic energy. Due to the presence of high kinetic energy, these molecules leave the surface and convert into vapors. Hence, evaporation is classified as a surface phenomenon.