Question

Evaporation takes place at/in
i.Boiling point
ii.Freezing point
iii.Between the freezing point and boiling point

Answer 1

Hint: Evaporation is a type of surface phenomenon defined as the process of conversion of molecules of liquid into their gaseous state. Evaporation is a type of endothermic process because it requires the source of energy to initiate the process.

Complete answer:
Any liquid compound has the ability to evaporate and convert into its vapour phase.
The boiling point of any substance is determined by observing the vapour pressure of the given liquid and atmospheric pressure. On the application of heat when a specific temperature is reached, when vapour pressure exerted by liquid comes in equilibrium with atmospheric pressure the process of boiling starts.
The process of freezing is defined as the process of conversion of liquid molecules into solid on lowering the temperature of liquid.
During the process of evaporation liquid molecules gain some energy from the heat supplied and get converted into gaseous state. This occurs because the kinetic energy of a molecule increases.
The molecules which are present at the surface of liquid have a tendency to attain high kinetic energy and escape the liquid.

Hence, we see that the process of evaporation occurs over a wide range of temperatures and there is no specific temperature for the process of evaporation as in the case of boiling and freezing.
Above discussion tells that any liquid undergoes the process of evaporation from its freezing point up to its boiling point.
Hence, option (iii) is the correct option.

Note:
Evaporator is the electric device which is used to evaporate the volatile liquid to get concentrated product.
Some examples of evaporation include production of blood products by evaporating their solvent, manufacturing of biological products like insulin preparation also include evaporation.