US BACCARY UOLUU MUILLUIHR----With the help of a neat diagram indicate why the solution of a non-volatile solute should freeze at atemperature lower than the freezing point of the pure solvent.[Delhi 2001, 2 M)

US BACCARY UOLUU MUILLUIHR----With the help of a neat diagram indicate

1.	US BACCARY UOLUU MUILLUIHR----With the help of a neat diagram indicate why the solution of a non-volatile solute should freeze at atemperature lower than the freezing point of the pure solvent.[Delhi 2001, 2 M)
Answer» We know that in order to freeze a liquid, we have to lower the temperature. As the temperature lowers, the solution becomes more ordered as it moves toward the solid phase. This is an effect that works against the second law of thermodynamics. In short, entropy (disorder) likes to increase not decrease in the natural scheme of things. So if we have to lower the temperature to a certain point to freeze a pure solvent, when we add a solute we add to the entropy of the system, The mixture is more disordered than the pure. This additional amount of entropy must now be overcome to allow the liquid to change phases into a solid (become ordered). This means that the temperature will have to be even lower than before. Thus addition of any type of solute to a solvent will lower its freezing point.