1. Solid → Liquid is called: A) Freezing B) Melting (Answer: B) C) Condensation D) Sublimation 2. Liquid → Gas is called: A) Condensation B) Freezing C) Evaporation (Answer: C) D) Deposition 3. Gas → Liquid is called: A) Melting B) Condensation (Answer: B) C) Sublimation D) Evaporation 4. Solid → Gas is called: A) Evaporation B) Freezing C) Sublimation (Answer: C) D) Deposition 5. Which state of matter has the least energy? A) Gas B) Plasma C) Liquid D) Solid (Answer: D) 6. Which state of matter has a definite volume but no definite shape? A) Solid B) Liquid (Answer: B) C) Gas D) Plasma 7. Which state of matter has the most energy? A) Solid B) Liquid C) Gas D) Plasma (Answer: D) 8. A bond between a metal and a nonmetal is: A) Covalent B) Ionic (Answer: B) C) Metallic D) Hydrogen 9. A bond between two nonmetals is: A) Ionic B) Covalent (Answer: B) C) Metallic D) Nuclear 10. Mg₃N₂ is: A) Covalent B) Ionic (Answer: B) C) Neither D) Both 11. Which compound is covalent? A) NaCl B) MgO C) CO₂ (Answer: C) D) CaBr₂ 12. Ionic bonds form when electrons are: A) Shared B) Transferred (Answer: B) C) Destroyed D) Created 13. A + B → AB is which reaction type? A) Decomposition B) Single replacement C) Synthesis (Answer: C) D) Combustion 14. AB → A + B is which reaction type? A) Synthesis B) Decomposition (Answer: B) C) Double replacement D) Combustion 15. AB + CD → AD + CB is: A) Single replacement B) Decomposition C) Combustion D) Double replacement (Answer: D) 16. A hydrocarbon reacting with oxygen to form CO₂ and H₂O is: A) Synthesis B) Combustion (Answer: B) C) Decomposition D) Replacement 17. When balancing chemical equations, you may change: A) Subscripts B) Element symbols C) Coefficients (Answer: C) D) Charges 18

Melting

The process of a solid turning into a liquid.

Evaporation

The process of a liquid turning into a gas.

Condensation

The process of a gas turning into a liquid.

Sublimation

The process of a solid turning directly into a gas.

Solid

The state of matter with the least energy.

Liquid

The state of matter with a definite volume but no definite shape.

Plasma

The state of matter with the most energy.

Ionic Bond

A bond formed between a metal and a nonmetal.

Covalent Bond

A bond formed between two nonmetals.

Ionic Compound

A compound made up of ions, such as Mg₃N₂.

Covalent Compound

A compound characterized by covalent bonds, such as CO₂.

Electron Transfer

The process in which electrons are transferred to form ionic bonds.

Synthesis Reaction

A reaction type represented by A + B → AB.

Decomposition Reaction

A reaction type represented by AB → A + B.

Double Replacement Reaction

A reaction type represented by AB + CD → AD + CB.

Combustion Reaction

A reaction in which a hydrocarbon reacts with oxygen to produce CO₂ and H₂O.

Coefficients in Chemical Equations

The numbers that can be changed when balancing chemical equations.

Conservation of Mass

The principle that requires chemical equations to be balanced.