Question

How does adding a non-volatile solute to a pure solvent affect the freezing point of the pure solvent?

The solvent will have a lower freezing point.

The solvent will have a higher freezing point.

The solvent's freezing point will not be affected.

The solvent's freezing point will most likely change, but not in a predictable way.

Answer 1

@pooja195 @CausticSyndicalist

Answer 2

it drops the freezing-point because it prevents crystallization, look up colligative properties

Answer 3

These are representing colligative properties,according to Raoult's law when adding the non volatile solute to the pure solvet its vapour pressure is decreased,this is due to reduction of area on the surface of solvent by solute particles .hence no of solvent molecules escaping from the solvent surface is lowered .
so the vapour pressure of solution is decreased than that of the pure solvent.
second is also explained by this law,it says melting point is decreased ,in this case the solute particles distrupts the crystallisation ,and more kinetic energy is required to freeze the solution than that of pure solvent.
Third one here boiling point is increased on addition of nonvolatile solute.boiling poit is the temperatute at which the solvent starts to boil when its vapour presure is equal to its atmospheric pressur,so more heat energy is required to boil the solution than that of pure solvent.
the freezing and boiling point constants are specific to solvents,