Understanding Reaction Rates
A Grade 9 science worksheet exploring factors affecting the rate of chemical reactions.
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Understanding Reaction Rates
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Read each question carefully and answer to the best of your ability. Show all your work for calculations.
1. Which of the following factors generally increases the rate of a chemical reaction?
Decreasing temperature
Increasing reactant concentration
Removing a catalyst
Decreasing surface area
2. What is the role of a catalyst in a chemical reaction?
It is consumed during the reaction.
It increases the activation energy.
It provides an alternative reaction pathway with lower activation energy.
It shifts the equilibrium position of the reaction.
3. The minimum amount of energy required to initiate a chemical reaction is called the .
4. Crushing a solid reactant into a powder increases its , which generally speeds up the reaction rate.
5. According to collision theory, for a reaction to occur, reactant particles must collide with sufficient and correct orientation.
6. Increasing the temperature of a reaction always decreases its rate.
True
False
7. A higher concentration of reactants leads to more frequent collisions between particles, thus increasing the reaction rate.
True
False
8. Explain how increasing the surface area of a solid reactant affects the rate of a chemical reaction. Provide an example.
9. Describe two ways to increase the rate at which sugar dissolves in water.
Match each term with its correct definition.
10. Inhibitor
a. Substance that speeds up a reaction without being consumed
11. Activation Energy
b. Minimum energy needed for a reaction to occur
12. Catalyst
c. Substance that slows down or prevents a reaction