Final answer:
Crystallization occurs in a supersaturated solution when it contains more solute than can remain in solution at a given temperature. Adding a seed crystal catalyzes this process, causing the excess solute to quickly precipitate out as crystals.
option b is the correct
Step-by-step explanation:
The question which asks about which type of solution results in crystallization concerns the concept of saturated, unsaturated, and supersaturated solutions in Chemistry. The correct answer is a supersaturated solution, which is a solution that contains more than the maximum amount of solute that can be dissolved at a given temperature. When a seed crystal is added to it, or under certain conditions, crystallization occurs because the extra solute precipitates out of the solution.
A saturated solution contains the maximum amount of solute that can dissolve at a certain temperature and will not lead to crystallization unless conditions change.
An unsaturated solution has less solute than what can be dissolved, so it can still dissolve more solute without leading to crystallization. On the other hand, the supersaturated solution is not stable; when a seed crystal is added, it can quickly trigger recrystallization, where the excess solute comes out of the solution and forms crystals.
For example, sodium acetate can form a supersaturated solution when cooled from a saturated solution without crystallization. However, when a seed crystal is added or when the solution is disturbed, rapid crystallization occurs, and heat is released, marking this as an exothermic process.