Quiz: Solutions

Which of the following actions will increase the rate of dissolution of a solid solute into an aqueous solution?

• Stirring with a spoon

• Freezing the solute

• Decreasing the temperature

• Continuously adding more solute

The image shows two different samples of the same compound, calcium carbonate. There are two beakers full of water. One sample is added to each beaker. Which of the following options correctly compares the rate of dissolution of the samples?

• The calcium carbonate stones will dissolve slowly since they have a lower surface area than the calcium carbonate powder.

• The calcium carbonate stones and calcium carbonate powder will dissolve at the same rate since they have the same surface area.

• The calcium carbonate stones will dissolve quickly since they have a greater surface area than the calcium carbonate powder.

You have a solution of saltwater. Which statement best describes what happens when you perform a dilution by adding water?

• The concentration of the solution will increase.

• The concentration of the solution does not change.

• The concentration of the solution will decrease.

• The amount of solute increases.

Zahara needs to make a CuSO₄ solution as quickly as possible for class. Categorize the actions she could take to speed up or slow down the process of dissolving the CuSO₄ in an aqueous solution?

Groups:

(a) Increase Rate of Dissolution

,

(b) Decrease Rate of Dissolution

• Stir the copper sulfate to agitate the solution.

• Break up the crystal to allow more surface area to touch the solvent.

• Minimize the agitation of the solution.

• Leave the copper sulfat crystal in tact and drop into the solvent.

• Heat the solution to increase the kinetic energy of the particles.

• Decrease the temperature of the solution to reduce kinetic energy.

Identify the solvent in this solution. Describe two different ways you could increase the concentration of the solution. Explain what action should not be taken because it would decrease the concentration of the solution. Be sure to use terms such as solute and solvent in your answer.

To increase the ________ of a solution, a person would dissolve more ________ into the ________. Which words best complete the sentence?

• dilution; solvent; solute

• dilution; solute; solvent

• concentration; solute; solvent

• concentration; solvent; solute