Which principle explains why a given solution can only dissolve a certain amount of solute at a specific temperature?

• A. Diffusion principle
• B. Equilibrium principle
• C. Solubility equilibrium
• D. Concentration gradient

Answer: (C)

The concept of solubility equilibrium directly relates to the maximum amount of solute that can dissolve in a solvent at a specific temperature. This principle states that in a saturated solution, the rate at which the solute dissolves is equal to the rate at which it precipitates out of the solution. As temperature increases, the kinetic energy of the molecules also increases, allowing more solute to dissolve, which can shift the equilibrium point.

At a given temperature, there is a specific concentration of solute that is in balance with its undissolved counterpart. If you add more solute than the solubility limit, it will not dissolve but remain in the solid state because the system has reached its solubility equilibrium. Therefore, this principle effectively explains why each solution has a limit to how much solute it can dissolve at a specified temperature.