Solids are more soluble at higher temperatures. How does the solubility of most solid solutes in water change with increasing temperature?

Solids are more soluble at higher temperatures. How does the solubility of most solid solutes in water change with increasing temperature?

• A. Decrease
• B. First increase then decrease
• C. Increase
• D. Remains constant

Answer: (C)

When you dissolve a solid in water, the process is often endothermic, meaning it absorbs heat. As temperature rises, added heat provides more energy to break apart the solid’s crystal lattice and allow ions or molecules to be hydrated in solution. This shifts the dissolution equilibrium toward more dissolved species, so the solubility increases with temperature. The increase in entropy that accompanies dissolving a solid also helps drive the process at higher temperatures, making the overall free energy change more favorable. While some uncommon solutes can show little change or even a decrease in solubility with temperature, the typical trend for most solid solutes in water is that solubility increases as temperature goes up.

When you dissolve a solid in water, the process is often endothermic, meaning it absorbs heat. As temperature rises, added heat provides more energy to break apart the solid’s crystal lattice and allow ions or molecules to be hydrated in solution. This shifts the dissolution equilibrium toward more dissolved species, so the solubility increases with temperature. The increase in entropy that accompanies dissolving a solid also helps drive the process at higher temperatures, making the overall free energy change more favorable. While some uncommon solutes can show little change or even a decrease in solubility with temperature, the typical trend for most solid solutes in water is that solubility increases as temperature goes up.