Could somebody help me with a Chemistry question?

Question

Does the freezing point of a solution remain relatively constant throughout the freezing process?

Answer 1

Yes, the freezing point is fixed. It does not change based upon the starting temperature of the solution.

Answer 2

There is a lowering of freezing point with increasing concentration. For example, if a dilute salt solution is cooled, first some water crystallizes out as ice this increases the concentration of the liquid phase which has to be cooled some more before further freezing happens.. It goes on till virtually all the water separates as ice.

Answer 3

Yes it does. In order to freeze a sample, energy must be removed form the material. The energy lost forces the molecules to rearrange themselves into a new phase of matter that is appropriate for the final temperature of the system.

Reb is correct. What I said applies to pure materials, however you asked about solutions which means that you have more than one component. So the freezing point will change over time as Reb correctly indicates.

Answer 4

The above answers are only correct for a pure substance. A solution is a mixture of substances. As such, the freezing point will not stay perfectly constsnt during the freezing phase change. It will drift lower as the concentration of the solution changes slightly during the freeze step.