Question

which factor causes a decrease in the rate of dissolution?
○ decreasing the amount of solute
○ increasing the sliming of the solution
○ decreasing the surface area of the solute
○ increasing the temperature of the solvent

Explanation:

• For "decreasing the amount of solute": The amount of solute doesn't directly affect the rate of dissolution (how fast it dissolves), just how much can dissolve (solubility limit in some cases), so this is incorrect.
• For "increasing the sliming of the solution" (assuming it's a typo, maybe "stirring"? If it's stirring, increasing stirring increases dissolution rate; if it's a different term, the option is unclear, but other options are more straightforward).
• For "decreasing the surface area of the solute": The rate of dissolution depends on how much surface area of the solute is in contact with the solvent. Smaller surface area (e.g., using a larger, less - broken - up solute) means less area for solvent - solute interaction, so the rate of dissolution decreases.
• For "increasing the temperature of the solvent": Increasing temperature generally increases the rate of dissolution as molecules have more kinetic energy to interact and break apart the solute, so this is incorrect.

Answer:

C. decreasing the surface area of the solute