Question

During the extraction of ink (colored substance from the liquid ink), the principle of separation involved is _________.
A. evaporation
B. condensation
C. sublimation
D. boiling

Answer 1

Hint: Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. The surrounding gas must not be saturated with the evaporating substance. When the molecules of the liquid collide, they transfer energy to each other based on how they collide with each other. When a molecule near the surface absorbs enough energy to overcome the vapor pressure, it will escape and enter the surrounding air as a gas.

Complete answer:
Evaporation is an endothermic process, in that heat is absorbed during evaporation. When heat is absorbed by the liquid ink, the molecules get excited and there is a rise in temperature and the bonds start breaking away and the water is released, leaving behind the dry ink.
During the extraction of ink which is actually the colored substance from the liquid ink, the principle of separation involved is evaporation. In this process, the ink is heated over the water bath. When water starts boiling, it starts heating the ink. In this process, the liquid component of ink gets evaporated leaving behind only dye. Evaporation is the loss of the liquid component from the ink leaving behind the colored component of the ink.

Thus, the correct option is A.

Note:
There are various applications of evaporation in day to day lives. They are as follows:
(i) Industrial applications include many printing and coating processes; recovering salts from solutions; and drying a variety of materials such as lumber, paper, cloth and chemicals.
(ii) The use of evaporation to dry or concentrate samples is a common preparatory step for many laboratory analyses such as spectroscopy and chromatography. Systems used for this purpose include rotary evaporators and centrifugal evaporators.
(iii) When clothes are hung on a laundry line, even though the ambient temperature is below the boiling point of water, water evaporates.