Which factor increases the rate of dissolution in an unsaturated solution?

• A. Decreasing the surface area of the solute
• B. Reducing agitation or stirring
• C. Using a solvent with lower polarity
• D. Increasing the temperature of the solvent

Answer: (D)

Verified step by step guidance

1. Understand that the rate of dissolution depends on factors that affect how quickly solute particles interact with the solvent.
2. Recognize that increasing the surface area of the solute (e.g., by crushing it) exposes more particles to the solvent, increasing the rate of dissolution, so decreasing surface area would reduce the rate.
3. Know that agitation or stirring helps distribute solute particles throughout the solvent, increasing contact and speeding up dissolution, so reducing stirring slows the rate.
4. Consider the polarity of the solvent: a solvent with polarity similar to the solute generally dissolves it better; using a solvent with lower polarity usually decreases the rate of dissolution for polar solutes.
5. Recall that increasing the temperature of the solvent increases the kinetic energy of molecules, leading to more frequent and energetic collisions between solute and solvent particles, thus increasing the rate of dissolution.