Final answer:
The solution with 37g KCl in 100 ml water at 20°C will be saturated as it exceeds the solubility limit of KCl at this temperature, which is 34g.
Step-by-step explanation:
When determining whether a solution is unsaturated, saturated, or supersaturated, solubility data at specific temperatures is essential. According to the given data, the solubility of KCl in 100 ml of water is 34g at 20 degrees Celsius. If 37g of KCl is added to the water at this temperature, the amount of KCl exceeds its solubility limit of 34g, meaning the solution would be saturated with 3g of excess KCl likely remaining as undissolved solid.
Exploring the scenarios provided as examples for other solutes, we understand that temperatures play a crucial role in solubility: heating generally increases solubility, allowing more solute to dissolve and making a previously saturated solution become unsaturated. Conversely, cooling a solution can lead to excess solute crystallizing out, resulting in reformation of a saturated solution from a supersaturated state.