You currently have JavaScript disabled on this browser/device. JavaScript must be enabled in order for this website to function properly.

ZingPath: Characteristics of Reactions

Factors Affecting the Rate of Chemical Reactions

Searching for

Characteristics of Reactions

Learn in a way your textbook can't show you.
Explore the full path to learning Characteristics of Reactions

Lesson Focus

Factors Affecting the Rate of Chemical Reactions

Chemistry

Learning Made Easy

You will explore the effects of temperature, amount of reactant, surface area, and catalysts on the rate of chemical reactions by participating in and observing a series of experiments.

Over 1,200 Lessons: Get a Free Trial | Enroll Today

Now You Know

After completing this tutorial, you will be able to complete the following:

  • Explain that as the amount of reactants in a chemical reaction increases, the rate of the reaction increases.
  • Describe that temperature usually is directly proportional to the rate of reaction.
  • Describe the surface area of the reactants as directly proportional to the rate of reaction.
  • Explain that the use of an appropriate catalyst can increase the rate of a chemical reaction.
  • Explain why the amount of reactant, temperature, surface area, and catalysts affect the rate of a chemical reaction.

Everything You'll Have Covered

The rate of reaction measures how fast a reactant is consumed and a product is formed. A rate law is the expression of this reaction as a result of the product produced over time. Multiple factors can affect the rate of reaction. Three factors we will talk about are temperature, surface area, and catalysts.

The amount of reactant may affect the rate of reaction. The amount of reactant can determine the rate of reaction because if there is less reactant available, the reaction will slow. If all the reactants are used, the reaction will stop. If the amount of reactant increases, the rate of reaction will also increase. An increase in reactants causes an increased rate of reaction because there is more opportunity for a reaction to occur.

If the temperature increases, the rate of reaction will also increase because molecular motion increases. The reverse is also true. If the temperature decreases, the rate of reaction will also decrease because molecular motion decreases. Refrigeration is an example of this. We refrigerate foods to prevent spoilage. What we are doing when we refrigerate foods is slowing the reactions that occur that break down perishable food. Slowing molecule speed will reduce the opportunities for collisions to occur. Therefore, the rate of reaction will decrease.

Surface area is another factor that affects the rate of reaction. The smaller the surface area, the faster the reaction will occur. If the surface area is large, the rate of reaction will be slower. This occurs because there is more opportunity for reactions to happen with a smaller surface area. As the frequency of the reactions increases, the rate of the reaction also increases.

The presence of a catalyst is another factor that affects the rate of reaction. It increases the rate of reaction, though it is not being consumed itself. Catalysts have the ability to change the way a reaction occurs. They can decrease the amount of activation energy needed and, in turn, increase the rate of reaction.

Tutorial Details

Approximate Time 20 Minutes
Pre-requisite Concepts Learners should have prior knowledge of how catalysts speed up chemical reactions while remaining unchanged.
Course Chemistry
Type of Tutorial Experiment
Key Vocabulary 3D, amount of reactants, catalyst