AP Chemistry Practice Quiz: Solutions and Mixtures

Written by AP Content Team, Verified for 2026 AP Exams, Last updated: May 2026

Test your understanding with short quizzes. This quiz has 9 questions to check your progress.

Question 1 of 9

Which of the following best describes a solution?

A)A mixture whose properties are inconsistent and vary with location.B)A pure substance that exists only in the liquid phase.C)A homogeneous mixture with uniform macroscopic properties.D)A mixture that can only be formed by dissolving a solid in a liquid.

All Questions (9)

Which of the following best describes a solution?

A) A mixture whose properties are inconsistent and vary with location.

B) A pure substance that exists only in the liquid phase.

C) A homogeneous mixture with uniform macroscopic properties.

D) A mixture that can only be formed by dissolving a solid in a liquid.

Correct Answer: C

Based on the provided content, solutions are defined as homogeneous mixtures that have uniform macroscopic properties. Heterogeneous mixtures have properties that vary with location.

A student prepares a solution by dissolving 3.0 moles of a solute into enough water to make a final volume of 6.0 L. What is the molarity of the solution?

A) 0.50 M

B) 2.0 M

C) 9.0 M

D) 18.0 M

Correct Answer: A

Molarity is calculated as moles of solute divided by liters of solution. M = 3.0 moles / 6.0 L = 0.50 M.

A sample of oil and water is shaken vigorously. After a few minutes, the oil and water separate into distinct layers. This sample is best classified as which of the following?

A) A gaseous solution

B) A homogeneous mixture

C) A solid solution

D) A heterogeneous mixture

Correct Answer: D

Because the properties of the mixture vary with location (an oil layer and a water layer), it is a heterogeneous mixture, not a solution.

How many moles of solute are present in 2.0 L of a 1.5 M solution?

A) 0.75 moles

B) 1.3 moles

C) 3.0 moles

D) 3.5 moles

Correct Answer: C

The molarity formula (M = moles/L) can be rearranged to solve for moles: moles = M × L. Therefore, moles = 1.5 M × 2.0 L = 3.0 moles.

The provided content states that solutions can exist as solids, liquids, or gases. Which of the following is an example of a solid solution?

A) Air (a mixture of nitrogen, oxygen, etc.)

B) Saltwater

C) Metal alloys, like brass

D) Sand in water

Correct Answer: C

Air is a gaseous solution and saltwater is a liquid solution. Sand in water is a heterogeneous mixture. Metal alloys are homogeneous mixtures of solids, making them solid solutions.

What volume of a 4.0 M solution is needed to provide 2.0 moles of solute?

A) 0.50 L

B) 2.0 L

C) 6.0 L

D) 8.0 L

Correct Answer: A

The molarity formula (M = moles/L) can be rearranged to solve for volume: L = moles / M. Therefore, L = 2.0 moles / 4.0 M = 0.50 L.

A student dissolves 0.25 moles of a salt in water to make 500. mL of solution. What is the molarity of this solution?

A) 0.00050 M

B) 0.50 M

C) 2.0 M

D) 125 M

Correct Answer: B

First, convert the volume from milliliters to liters: 500. mL = 0.500 L. Then, use the molarity formula: M = moles / L = 0.25 moles / 0.500 L = 0.50 M.

A student observes a clear, blue copper(II) sulfate solution in a beaker. If samples are taken from the top, middle, and bottom of the beaker, which property is expected to be the same for all samples?

A) The total number of water molecules in each sample.

B) The total mass of each sample.

C) The molarity of the solution.

D) The location from which the sample was taken.

Correct Answer: C

A solution is a homogeneous mixture, meaning its macroscopic properties are uniform throughout. Molarity, a measure of concentration, is a macroscopic property and should be consistent regardless of where the sample is taken from.

The composition of a solution is most commonly expressed as molarity because this unit provides a direct relationship between which two quantities?

A) The mass of the solute and the mass of the solvent.

B) The volume of the solute and the volume of the solution.

C) The number of solute particles (moles) and the total volume of the solution (L).

D) The number of solute particles (moles) and the total mass of the solution (kg).

Correct Answer: C

Molarity (M) is defined as moles of solute per liter of solution (M = moles_solute / L_solution). This directly relates the amount of solute in moles to the total volume of the solution.