Which of the following actions would increase the rate at which NaCl dissolves in water?

• A. Stirring the solution
• B. Decreasing the temperature of the water
• C. Using larger salt crystals
• D. Adding more salt to the water

Answer: (A)

Verified step by step guidance

1. Understand that the rate of dissolution depends on factors such as surface area, temperature, agitation (stirring), and concentration of the solute in the solvent.
2. Recognize that stirring the solution increases the interaction between the solute (NaCl) and solvent (water) by moving fresh solvent to the surface of the salt crystals, which speeds up dissolution.
3. Note that decreasing the temperature generally slows down the rate of dissolution because molecular motion decreases, reducing the interaction between solute and solvent.
4. Understand that using larger salt crystals decreases the surface area available for dissolution, which slows down the rate compared to smaller crystals or powdered salt.
5. Realize that adding more salt to the water increases the concentration of solute, which can slow down the rate of dissolution as the solution approaches saturation.