Final answer:
Higher temperatures often increase the solubility of solid substances in a solution by giving the solvent molecules more energy, leading to more effective collisions with the solute. An example is sugar dissolving better in hot water. However, for gases, higher temperatures usually decrease solubility.
Step-by-step explanation:
Generally, higher temperatures increase the amount of a solid substance that can be dissolved in a solution. This is due to the increased kinetic energy that the solvent molecules gain as they heat up, causing them to collide more frequently and with greater force against the solute. This enhanced collision rate speeds up the dissolution process and usually means that a greater amount of the solute can dissolve. A classic example is the increased solubility of sugar in hot water compared to cold.
However, the relationship between solubility and temperature is not uniform across all substances. For gases, solubility typically decreases as temperature increases. This temperature-solubility relationship is often depicted in a solubility curve. The curve shows how the solubility of substances changes with temperature, indicating a general trend but not being universally applicable to all solutes.