AP Chemistry Practice Quiz: Physical and Chemical Changes
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
All Questions (9)
A) Chemical processes are always irreversible, while physical processes are always reversible.
B) Chemical processes involve breaking or forming chemical bonds, while physical processes involve changes in intermolecular interactions.
C) Chemical processes change a substance's state of matter, while physical processes change its color.
D) Chemical processes occur only in solids, while physical processes occur in liquids and gases.
Correct Answer: B
The content explicitly states that 'Chemical processes involve breaking/forming chemical bonds. Physical processes involve changes in intermolecular interactions.' This is the core distinction provided.
A) Chemical bonds within the H₂O molecules are broken.
B) New chemical bonds are formed, creating a different substance.
C) Intermolecular interactions between H₂O molecules are overcome.
D) Ion-dipole interactions are formed between separated H⁺ and OH⁻ ions.
Correct Answer: C
Melting is a phase change, which is a physical process. According to the text, physical processes involve changes in intermolecular interactions, not the breaking of chemical bonds within the molecules themselves.
A) The particles must have simply rearranged themselves into a more ordered structure.
B) The intermolecular forces between the particles must have weakened.
C) Chemical bonds must have been broken and/or new chemical bonds formed.
D) The substance must have undergone a phase change from liquid to solid.
Correct Answer: C
The text establishes a direct relationship between macroscopic changes in a chemical process and the microscopic event of breaking or forming chemical bonds, which results in a new substance.
A) Because the final solution has different physical properties than pure water.
B) Because the process involves the breaking of ionic bonds within the salt's crystal lattice.
C) Because the salt can be recovered by evaporating the water, making it a reversible process.
D) Because only intermolecular forces are altered during the dissolution.
Correct Answer: B
The text identifies dissolving a salt as ambiguous because it involves breaking chemical bonds (ionic bonds). Since the definition of a chemical process is the breaking/forming of chemical bonds, this aspect supports the argument for it being a chemical change.
A) Because a new, covalently bonded substance is formed.
B) Because the process is always accompanied by a large release of energy.
C) Because it involves the formation of new ion-dipole interactions, which is a change in inter-particle forces.
D) Because the ionic bonds in the salt lattice remain completely intact.
Correct Answer: C
The text states that physical processes involve changes in intermolecular interactions. The formation of new ion-dipole interactions between the ions and water molecules fits this description, supporting the argument that dissolving is a physical process.
A) The combustion of wood.
B) The rusting of an iron pipe.
C) The condensation of steam on a cold window.
D) The dissolving of sodium chloride in water.
Correct Answer: C
Condensation is a phase change (gas to liquid). The text uses phase changes as a key example of a physical process, which involves changes in intermolecular interactions without altering the chemical identity (H₂O remains H₂O). The other options are chemical changes or the ambiguous case.
A) the distance between particles changes.
B) the fundamental identity of the substance's particles has changed.
C) the process is always endothermic.
D) the particles are moving at a faster speed.
Correct Answer: B
The content links chemical processes to the breaking and forming of chemical bonds. This action creates new substances with different chemical identities, which in turn exhibit different macroscopic characteristics (e.g., color, reactivity).
A) It is a simple physical process where only intermolecular forces between water molecules are affected.
B) It is a simple chemical process where ionic bonds are broken and new covalent bonds are formed.
C) It is a complex process involving the breaking of chemical (ionic) bonds and the formation of new inter-particle (ion-dipole) interactions.
D) It is neither a physical nor a chemical process, as no bonds or interactions are altered.
Correct Answer: C
This option correctly synthesizes all the information given about the ambiguous case of dissolving a salt. The text explicitly mentions that it involves both breaking chemical (ionic) bonds and forming new interactions (ion-dipole), making this the most comprehensive and accurate description.
A) Ionic bonds
B) Covalent bonds
C) Intermolecular interactions
D) Ion-dipole interactions
Correct Answer: C
The content explicitly identifies phase changes as examples of physical processes. It then defines physical processes as those that 'involve changes in intermolecular interactions.'