MCQ Detailed View

In crystallization, a common method for purifying solid compounds, crystals form from a saturated solution as the solute precipitates. The solution that remains after the crystals have formed is called the mother liquor. This solution still contains dissolved solute that did not crystallize.

The mother liquor is important in laboratory processes because it can sometimes be reused to extract additional crystals. Its composition can also provide information about the purity of the substance and the solubility of the compound in the solvent. By careful control of temperature and solvent choice, chemists maximize the yield of crystals while leaving minimal solute in the mother liquor.

Other options in the question are incorrect. A dilute solution refers to a solution with a small amount of solute relative to solvent, which is not specific to crystallization. Residue usually refers to the solid left behind after filtration, which is the opposite of the solution remaining. Option D (“Both A & B”) is incorrect because only the term mother liquor precisely describes the solution left after crystallization.

Understanding the concept of mother liquor is important in organic chemistry and laboratory techniques. It is widely applied in chemical industries, pharmaceutical manufacturing, and research labs where purification of compounds is critical. Chemists often analyze mother liquor for residual impurities or uncrystallized solute, which helps in improving crystallization efficiency.

The term mother liquor is therefore the correct designation for the solution that remains after crystals have formed, highlighting a key concept in crystallization, purification, and practical organic chemistry.