Understanding Solutions and Concentration

Which of the following best describes a solute in an aqueous solution?

• The substance that dissolves another substance

• The substance that is dissolved in water

• The liquid that forms the solution

• The gas released during mixing

Answer explanation

A solute is defined as the substance that is dissolved in a solvent, which in this case is water. Therefore, the correct choice is 'The substance that is dissolved in water', as it accurately describes the role of a solute.

What is the solvent in a solution of saltwater?

• Salt

• Water

• Air

• Sugar

Answer explanation

In a saltwater solution, water acts as the solvent, dissolving the salt. Salt is the solute, while air and sugar are not components of this solution.

If you add more solute to a fixed amount of solvent, what happens to the concentration of the solution?

• It decreases

• It increases

• It stays the same

• It evaporates

Answer explanation

When you add more solute to a fixed amount of solvent, the amount of solute per unit volume increases, leading to a higher concentration of the solution. Therefore, the correct answer is that the concentration increases.

Which of the following is an example of dilution?

• Adding more sugar to tea

• Adding water to orange juice

• Heating a solution

• Freezing a solution

Answer explanation

Adding water to orange juice is an example of dilution because it decreases the concentration of the juice by increasing the total volume with a less concentrated liquid, making the flavor less intense.

• Water

• Salt

• Both water and salt

• Neither

Answer explanation

In this scenario, the solute is the substance that is dissolved in the solvent. Here, salt is dissolved in water, making salt the solute. Therefore, the correct answer is salt.

What happens to the concentration of a solution if you add more solvent but keep the amount of solute the same?

• It increases

• It decreases

• It stays the same

• It becomes saturated

Answer explanation

When you add more solvent while keeping the solute constant, the total volume of the solution increases. This results in a lower concentration of solute per unit volume, so the concentration decreases.

Which statement is true about an aqueous solution?

• The solvent is always oil

• The solvent is always water

• The solute is always a gas

• The solute is always a solid

Answer explanation

In an aqueous solution, the solvent is always water. This distinguishes it from other types of solutions where different solvents may be used. The other statements are incorrect as they do not accurately describe aqueous solutions.

If you have a solution with a high concentration of solute, it means:

• There is a lot of solvent compared to solute

• There is a lot of solute compared to solvent

• The solution is always colorless

• The solution is always hot

Answer explanation

A high concentration of solute indicates that there is a lot of solute compared to the amount of solvent. This means the correct choice is that there is a lot of solute compared to solvent.

Which of the following would make a solution more dilute?

• Adding more solute

• Removing some solvent

• Adding more solvent

• Heating the solution

Answer explanation

Adding more solvent increases the volume of the solution while keeping the amount of solute constant, resulting in a more dilute solution. The other options either increase solute concentration or do not affect dilution.

• Sugar

• Water

• Both sugar and water

• Neither

Answer explanation

In a solution, the solvent is the substance that dissolves the solute. Here, water is the solvent as it dissolves the sugar, which is the solute. Therefore, the correct answer is water.