seperating substances..?

Question

if...
Solid X is soluble in both hot water and cold water
Solid Y is soluble in hot water but not in cold water
Solid Z is insoluble in hot and cold water

how would you seperate 'Solid Y' from a mixture of X, Y and Z.

Answer 1

By adding the mixture of X, Y, and Z to water and attempting to dissolve the three substances in hot water, only two will dissolve (X and Y, Z will not dissolve). You can filter the solution to remove the Z particles, leaving behind only a solution of X and Y.

You can this cool the solution down. Since Y is only soluble in hot water, it will precipitate out when the solution is cooled. X is soluble in both hot and cold water so it will remain behind in solution allowing you to filter out the Y particles.

In this manner you could separate substance Z first from the X, Y, Z mixture, then separate Y from X.