Unit 8: Chemical Reactivity
- What is the main factor that affects the rate of a chemical reaction?
- A) Color of the reactants
- B) Temperature
- C) Shape of the container
- D) Volume of the container
- Answer: B) Temperature
- Which of the following is a catalyst in the Haber process?
- A) Iron
- B) Copper
- C) Platinum
- D) Nickel
- Answer: A) Iron
- What does the term “activation energy” refer to?
- A) The energy needed to start a reaction
- B) The energy released during a reaction
- C) The energy needed to break bonds
- D) The energy needed to form bonds
- Answer: A) The energy needed to start a reaction
- In which type of reaction is heat released to the surroundings?
- A) Endothermic
- B) Exothermic
- C) Isothermal
- D) Hyperthermic
- Answer: B) Exothermic
- Which factor does not affect the rate of a chemical reaction?
- A) Concentration of reactants
- B) Temperature
- C) Presence of a catalyst
- D) Color of the reactants
- Answer: D) Color of the reactants
- What is formed when an acid reacts with a base?
- A) Salt and water
- B) Salt and carbon dioxide
- C) Water and hydrogen gas
- D) Salt and sulfur dioxide
- Answer: A) Salt and water
- What is the term for a reaction that occurs without external input of energy?
- A) Spontaneous reaction
- B) Non-spontaneous reaction
- C) Endothermic reaction
- D) Catalytic reaction
- Answer: A) Spontaneous reaction
- Which of the following elements is most reactive?
- A) Hydrogen
- B) Helium
- C) Sodium
- D) Argon
- Answer: C) Sodium
- What happens to the rate of a reaction if the concentration of reactants is increased?
- A) It decreases
- B) It remains the same
- C) It increases
- D) It becomes zero
- Answer: C) It increases
- In which type of reaction are new substances formed?
- A) Physical change
- B) Chemical change
- C) Phase change
- D) Dissolution
- Answer: B) Chemical change