Question

Camphor is separated from $NaCl$ by the method.
A. Sublimation.
B. Distillation.
C.Sedimentation.
D. Evaporation.

Answer 1

We know that if there is a change temperature or pressure of the system phase also get changed. We must remember if the temperature or pressure increases the interaction between molecules also increases. Likewise, if the temperature or pressure decreases molecules move freely and the atoms settle into a more rigid structure.

Complete step by step answer: Now, we see the sublimation process.
Sublimation is the process in which solids directly change to gases. Sublimation occurs if solids absorb enough energy to overcome the forces of attraction between them.
Example: Dry ice is solid which undergo sublimation.
If a mixture of $NaCl$ and camphor is heated, camphor sublimes and its vapors are obtained.
The vapors on cooling condensed into solid. By sublimation process camphor is separated from $NaCl$.
$\therefore$, option A is correct.
Let us discuss the distillation method as,
Distillation: This method is used to separate the components of a mixture containing two miscible liquids. In this method, the liquid mixtures are boiled, vaporized, condensed and isolated.
$\therefore$, option (B) is incorrect.
Now we discuss about sedimentation process as,
Sedimentation: It is a technique in which heavier impurities in water are settled down at the bottom of the apparatus. The constituent which is settled down is called sediment and the water which is present above sediment is called supernatant.
$\therefore$, option C is incorrect.
Evaporation: This method is used to separate the mixtures in which solvent is liquid and the solute is soluble solid.
$\therefore$, the option D is incorrect.

Note: We also know that the camphor is also separated from sodium chloride by filtration method if the mixture is dissolved in water. Sodium chloride dissolves and camphor remains as residue. Camphor is then separated by filtration and the sodium chloride is recovered from water through evaporation.