Caffeine is about 10 times as soluble in hot water as in cold water. A chemist puts a hot-water extract of caffeine into an ice bath, and some caffeine crystallizes. Is the remaining solution saturated, unsaturated, or supersaturated and why?

Supersaturated solution

Explanation:

A super-saturated solution is on that contains more than the amount of solute needed to saturate it at a particular temperature.

In our problem, Caffeine solution was saturated when it was in hot water because it was at a temperature where the solubility is high. Immediately it was introduced to an ice bath, a new temperature is recorded. At that lower temperature only a very less amount of caffeine is needed to saturate the solution, hence the excess crystallizes out and makes the solution super-saturated