Name: ______________________ Class: _________________ Date: _________
ID: A
Chemical Reactions Test Review
Multiple Choice
Identify the choice that best completes the statement or answers the question.
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1. Which of the following is NOT a correct inference that you can make about the burning of wood?
a. Energy is released at heat.
b. New substances are produced, such as smoke.
c. The reaction is a physical change.
d. Chemical bonds are broken and others are formed.
2. CaCO3 represents a chemical
a. symbol.
b. reaction.
c. subscript.
d. formula.
3. The only sure evidence for a chemical reaction is
a. changes in properties.
b. the formation of a gas.
c. a color change.
d. the production of one or more new substances.
4. A shorter, easier way to show chemical reactions, using symbols instead of words, is called a
a. symbol.
b. chemical formula.
c. chemical equation.
d. subscript.
5. Which of the following does NOT increase the number of particles of a substance available to react in
a chemical reaction?
a. adding a catalyst
b. increasing the surface area
c. increasing the mass
d. increasing the concentration
6. Which of the following is an example of how to supply activation energy to begin a reaction?
a. Cool the reaction flask in an ice bath.
b. Heat the reaction flask on a hot plate.
c. Add a catalyst.
d. Add an inhibitor.
7. What is the best form of fire safety?
a. a water hose
b. an extinguisher
c. the fire department
d. fire prevention
8. The best way to put out a small kitchen fire is to
a. blow it out.
b. use a garden hose.
c. turn off the appliances.
d. cover it or use a home fire extinguisher.
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Name: ______________________
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ID: A
9. Every chemical reaction involves a change in
a. mass.
b. energy.
c. concentration.
d. state.
Modified True/False
Indicate whether the statement is true or false. If false, change the identified word or phrase to make the
statement true.
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10. A change that produces a new substance is a physical change. _________________________
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11. A chemical reaction may be detected by observing changes in the properties of matter.
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12. The amount of matter in a chemical reaction changes. _________________________
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13. Replacement is the process of making a more complex compound from simpler substances.
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14. The rate of a chemical reaction is independent of temperature. _________________________
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15. A gas necessary for combustion to take place is oxygen. _________________________
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16. A physical reaction happens when chemical bonds break and new bonds form.
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17. The substances listed on the left side of a chemical equation are the reactants and the substances on
the right are the products.
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18. The principle of conservation of mass is true only for closed system reactions.
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Name: ______________________
ID: A
Short Answer
Use the diagram to answer each question.
19. Is the reaction that occurs in the diagram endothermic or exothermic? Explain.
20. When the candle was lit, a pool of liquid wax formed in the area around the wick, and then spilled
over the side and resolidified. Does this observation refer to a physical change or a chemical change?
Explain.
21. If the candle is covered by a large glass beaker, the flame will go out. How does the beaker affect the
conditions described by the fire triangle?
22. If the products formed from the burning candle are mostly carbon (C), carbon dioxide (CO2), and
water (H2O), what elements were in the reactants? How do you know?
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Name: ______________________
ID: A
23. The flame from the candle gives off black smoke. Does this statement describe evidence for a
physical change or a chemical change? Explain.
24. Is a burning candle an example of an open system or a closed system? Explain.
Use the diagram to answer each question.
25. What type of chemical reaction is represented in the diagram? Explain.
26. Identify the reactant(s) and product(s) of the reaction.
27. How would the mass of water formed in the reaction compare to the mass of oxygen that reacts?
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Name: ______________________
ID: A
28. Where does the water come from in the reaction?
29. What is the purpose of the burning splint in the reaction?
30. Write a balanced equation for the reaction.
31. Balance the following equation. SHOW YOUR WORK.
_____ C + _____ H2
→
_____ C3H8
32. Balance the following equation. SHOW YOUR WORK.
_____ C2H2 + _____ H2
→
_____ C2H6
33. Define chemistry.
34. Define matter.
35. What type of reaction is FeS + 2 HCl → FeCl2 + H2S?
36. What does a balanced chemical equation show?
37. Define endothermic.
38. Define exothermic.
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Name: ______________________
ID: A
39. Define inhibitor.
40. Define the principle of conservation of mass.
41. Which two types of chemical reactions could be considered opposites? Why?
42. Define activation energy.
43. Define combustion.
44. Name three ways a fire be brought under control?
45. Define enzyme.
46. What do coefficients tell you?
47. Define subscript.
48. Define reactants.
49. Define products.
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