Question

at 40°c, 50g of KClO3 is dissolved in 100g of water, is this solution saturated, unsaturated, or supersaturated?

Answer 1

Answer:

Supersaturated

Explanation:

Let's define the types of solutions in the context of this problem firstly:

• An unsaturated solution is a solution in which addition of more solute would result in dissolution at a given specific temperature. That is, at $40^oC$, if we add more than 50 g of $KClO_3$ and it still dissolves in 100 g of water, then we have an unsaturated solution.
• A saturated solution is a solution in which we have a maximum amount of a solute that could possibly dissolve in a solvent at a given specific temperature. That is, at $40^oC$, if we add 50 g of $KClO_3$ and no more of it dissolves, then we have a saturated solution.
• A supersaturated solution is a solution in which we have a greater amount of solute dissolved than we could possibly dissolve under normal circumstances. Let's say that the solubility here is 50 g of $KClO_3$ in 100 g of water at $40^oC$. If we dissolve more than 50 g, then we have a supersaturated solution.

We need to use a solubility curve for salts given below. Notice that the intersection in the y-axis at $40^oC$ is at about 14 g. This means a saturated solution would be obtained if 14 g of $KClO_3$ were dissolved in 100 g of water at this temperature. Anything above it would yield a supersaturated solution, below – an unsaturated solution.

Hence, we have a supersaturated solution.