Humber Admissions Practice Test

What happens to the solubility of many solids as temperature increases?

1. It stays the same

2. It generally decreases

3. It generally increases

4. It is unpredictable

The correct answer is: It generally increases

As temperature increases, the solubility of many solid substances in a solvent typically increases. This phenomenon occurs because higher temperatures provide more energy to the molecules of the solute (the solid) and the solvent (the liquid), which helps to overcome the attractive forces between the particles of the solid. As a result, more solid can dissolve in the solvent. In many cases, this is especially evident in substances like table salt or sugar, where increased heat leads to a greater amount of solid being able to dissolve in water. The kinetic energy of the molecules rises with temperature, enhancing the interactions that allow for the disintegration of the solid’s structure into individual solute particles that are surrounded by solvent molecules. Some other substances may have different solubility behaviors that are influenced by specific chemical properties or interactions with the solvent. However, for the vast majority of typical solid solutes in water, the trend is that solubility increases with temperature. This principle is significant in various applications, including chemical reactions, cooking, and industrial processes where solute concentrations are critical.