Why does increasing temperature increase solubility

Consider the case where the solubility process is endothermic heat added. An increase in temperature puts a stress on the equilibrium condition and causes it to shift to the right. The stress is relieved because the dissolving process consumes some of the heat. Therefore, the solubility concentration increases with an increase in temperature.

If the process is exothermic heat given off. A temperature rise will decrease the solubility by shifting the equilibrium to the left. Solids and liquids show almost no change in solubility with changes in pressure.

But gases are very dependent on the pressure of the system. Gases dissolve in liquids to form solutions. This dissolution is an equilibrium process for which an equilibrium constant can be written. The form of the equilibrium constant shows that the concentration of a solute gas in a solution is directly proportional to the partial pressure of that gas above the solution.

This statement, known as Henry's law , was first proposed in by J. Henry as an empirical law well before the development of our modern ideas of chemical equilibrium. When you add a solute to a solvent , the kinetic energy of the solvent molecules overcomes the attractive forces among solute particles. The solute particles leave the surface of the solid and move into the dissolved aqueous phase.

As the salt dissolves, the positive and negative ions are pulled apart and become surrounded by water molecules. If we heat the solvent, the average kinetic energies of its molecules increases.

Hence, the solvent is able to dislodge more particles from the surface of the solute. Thus, increasing the temperature increases the solubilities of substances. For example, sugar and salt are more soluble in water at higher temperatures. But, as the temperature increases, the solubility of a gas in a liquid decreases. As temperature increases, the average kinetic energy of the gas molecules increases. Ernest Z. Jan 11, Related questions How can the formation of a solution be exothermic or endothermic?

How does the formation of a solution involve energy? How do you find heat of formation of a solution? Which factors promote the formation of solutions? This means that the solution will be saturated since 48 g is less than 80 g. Now the solution is unsaturated since it contains only the original 80 g of dissolved solute.

Skip to main content. Search for:. How Temperature Influences Solubility Learning Objectives Describe the influence of temperature on the solubility of solids in water.

Describe the influence of temperature on the solubility of gases in water. What happens to the fish in the water next to a nuclear power plant? Summary The solubility of a solid in water increases with an increase in temperature. Gas solubility decreases as the temperature increases.