Types of chemical reaction
Look at the pattern of each chemical equation and sort the reactions into combination, decomposition, displacement and double displacement.
Core concept
Reactions can be classified by how the reactants rearrange: A + B → AB, AB → A + B, A + BC → AC + B, and AB + CD → AD + CB
Topic: Chemical reactions
Chemical reactions can be grouped by the way atoms rearrange. In a combination reaction two or more substances join to make one product (A + B → AB). In a decomposition reaction one substance breaks down into two or more simpler ones (AB → A + B), usually needing heat, light or electricity. In a displacement reaction a more reactive element pushes a less reactive one out of its compound (A + BC → AC + B). In a double displacement reaction two compounds swap partners (AB + CD → AD + CB), often forming a precipitate or water.
What you will learn
- Recognise the four main types of chemical reaction from their equations.
- Describe the general pattern of each type.
- Give an everyday example of each.
Before you start
- Be able to read a balanced chemical equation.
Materials
- Equation cards
Equipment
- None for the virtual lab
Procedure
- Choose an equation card and look at its pattern: how many reactants and products, and which are elements?
- Place each card in the right reaction type.