Question

pellets of calcium chloride are spread on a sidewalk covered in water that is 30°c. under which circumstance will the calcium chloride dissolve faster? sand is sprinkled on the sidewalk. the water cools to a temperature of 33°c. people walking on the sidewalk crush the calcium chloride pellets. the air pressure increases as the weather changes.

Explanation:

The rate of dissolution of a solid in a liquid is affected by factors such as surface - area to volume ratio. Crushing the calcium chloride pellets (by people walking on them) increases their surface area, which speeds up the dissolution process. Sand sprinkling has no direct effect on dissolution, cooling the water slows down dissolution (as solubility of many salts decreases with decreasing temperature), and air - pressure change has little to no effect on the dissolution of calcium chloride in water at these conditions.

Answer:

People walking on the sidewalk crush the calcium chloride pellets.