In this activity, students will learn about some of the ways to classify different types of chemical reactions. It covers synthesis (combination), decomposition, single replacement (single displacement), double replacement (double displacement), combustion, and acid-base neutralization reactions.
Middle School, High School
This activity will help prepare your students to meet the performance expectations in the following standards:
- MS-PS1-1: Develop models to describe atomic composition of simple molecules and extended structures.
- Scientific and Engineering Practices:
- Developing and Using Models
By the end of this activity, students should be able to:
- Identify and describe some of the common categories used to classify reactions.
- Classify example reactions into these categories.
- Compare similarities and differences between reaction types.
- Research real-life examples of each type of reaction, as well as other types of reactions not presented in this animation.
This activity supports students’ understanding of:
- Types of chemical reactions
Teacher Preparation: minimal
Lesson: 10-30 minutes
- Computer and projector with internet access
- Student handout
- No specific safety precautions need to be observed for this activity.
- All of the animations that make up the AACT Animation collection are designed for teachers to incorporate into their classroom lessons. Intentionally, these animations do not have any spoken explanations so that a teacher can speak while the animation is playing, and stop the animation as needed to instruct.
- We suggest that a teacher pause this animation at several points, including when questions are posed before the answers are revealed, or watch it more than once to give students the opportunity to make notes, ask questions, and test their understanding of the concepts presented. The student activity sheet can help activate students’ prior knowledge, guide them through the animation, and provide a chance for after-viewing reflection and optional extension questions.
- Note that this animation does not attempt to show the mechanism by which these reactions occur and only intends to show the composition of reactants and products.
- States of matter are not indicated in the example reactions, and the activity series (for single replacement reactions) and solubility rules (double replacement reactions) are not addressed either. Depending on how much detail you want to provide, you may want to tell your students that not all reactions that look like single or double replacement reactions will actually occur.
- Be sure to emphasize that combustion reactions do not always contain CH4 but can involve any hydrocarbon, which will affect the coefficients used to balance the equation. It may be helpful to provide a couple other examples, and there is one in the “Test Your Knowledge” section as well.
- In the Acid-Base Neutralization section, students are asked to think about what other kind of reaction it looks similar to (double replacement), and there is a question in the student handout that asks them to look at similarities between the different reaction types that could potentially be confusing. The answer key provides several possibilities, but students may come up with others as well. This might be a good topic for a class discussion and could lead into an explanation of how these categories are not perfect or all-inclusive but do give us a general outline for grouping many common reactions. There is also a question on the student handout that asks students to research another reaction category not described in this animation, which could be included in this discussion as well.
- There are several different ways to classify equations – the types of reactions in this animation are commonly taught in introductory chemistry courses, but another approach includes identifying reactions as redox, precipitation, or acid-base neutralization. In the question on the student handout mentioned previously, students will have the opportunity to explore other ways of categorizing equations.
- Here are several of the classroom resources from the AACT Library that may be used to further teach these topics:
For the Student
- Take notes on each of the following types of reactions presented in the animation:
- Synthesis (Combination)
- Single Replacement (Single Displacement)
- Double Replacement (Double Displacement)
- Acid-Base Neutralization
- Classify the reactions in the “Test Your Knowledge” section of the animation:
|a) Zn + CuSO4 → Cu + ZnSO4||__________________________________|
|b) HBr + NaOH → NaBr + H2O||__________________________________|
|c) C3H8 + 5O2 → 3CO2 + 4H2O||__________________________________|
|d) PbBr2 → Pb + Br2||__________________________________|
- Are there any similarities between any of the reaction categories that would make it hard to tell whether a reaction belonged to one category or another? Explain how you would differentiate between them.
- These ones don’t look exactly like the ones in the animation, but what category do you think makes the most sense for them? Justify your classification.
- C2H5OH + 3O2 → 2CO2 + 3H2O
- P4 + 5O2 + 6H2O → 4H3PO4
- 2NaHCO3 → CO2 + Na2CO3 + H2O
- CO2 + H2O → H2CO3
- Look up a real-world reaction (one that was not used in the animation) for each category presented in the animation. Explain how that reaction is used in nature or an industrial application. Cite your sources appropriately.
- The reaction types presented in the animation are not the only way to categorize reactions. Do some research and find at least one other kind of reaction that is not mentioned in the animation and briefly describe that reaction type in your own words. (Again, be sure to list your sources!) Does it overlap with any of the categories described in the animation?