Understanding Chemical Reactions
Chemical reactions can seem overwhelming, but they all follow predictable patterns. There are 5 main types of chemical reactions that you'll encounter in chemistry class.
💡 Pro Tip: Once you recognize the pattern, you can predict products and balance equations much faster!
1 Synthesis Reactions (Combination)
Pattern: A + B → AB
Two or more simple substances combine to form a more complex compound.
Examples:
2 Decomposition Reactions
Pattern: AB → A + B
A complex compound breaks down into simpler substances. Often requires heat or electricity.
Examples:
3 Single Displacement Reactions
Pattern: A + BC → AC + B
One element replaces another element in a compound. The more reactive element "kicks out" the less reactive one.
Examples:
4 Double Displacement Reactions
Pattern: AB + CD → AD + CB
Two compounds exchange ions. Often produces a precipitate, gas, or water.
Examples:
5 Combustion Reactions
Pattern: CₓHᵧ + O₂ → CO₂ + H₂O
A hydrocarbon (or organic compound) reacts with oxygen to produce carbon dioxide and water. Always releases energy!
Examples:
Quick Reference Guide
Synthesis
A + B → AB
Combine to build
Decomposition
AB → A + B
Break apart
Single Displacement
A + BC → AC + B
One swap
Double Displacement
AB + CD → AD + CB
Double swap
Combustion
CₓHᵧ + O₂ → CO₂ + H₂O
Burn with oxygen
Ready to Practice?
Test your knowledge with our interactive chemical equation balancer!