1. Types of Reactions
Science 10

2. Chemists classify reactions to make them easier to predict the products of reactions and recognize new reactions.
There are five types of reactions:

3. General Formula is: A + B  AB
1. Synthesis Reaction:
- Also called combination reactions.
- Involves the combination of smaller atoms and/or molecules into larger molecules
- Often two elements combining to make a compound
General Formula is: A + B  AB
Example: Mg N2  Mg3N2

5. General Formula is: AB  A +B
2. Decomposition Reaction:
- Involves the splitting of a large molecule into elements or smaller molecules
General Formula is: AB  A +B
Example: NaCl  Na Cl2

7. A + BC  AC + B or D + EF  ED + F
3. Single Replacement Reaction:
- Involves an element and a compound as reactants
- One element displaces (replaces) another element from a compound
General Formula is:
A + BC  AC + B or D + EF  ED + F
(metal replacement) (halogen replacement)
(usually a metal replaces the other metal or the non-metal replaces the other non-metal)
Or Br + NaI  NaBr + I2
Example: Li + NaCl  LiCl + Na

9. General Formula is: AB + CD  AD + CB
4. Double Replacement Reaction:
- Occurs when elements in different compounds displace each other or exchange places.
General Formula is: AB + CD  AD + CB
Example: AgNO3 + Na2S  Ag2S NaNO3

11. General Formula is: C?H? + O2  CO2 + H2O
5. Combustion Reaction:
- Is the burning of something
- Oxygen is always a reactant!
- If there is combustion of a hydrocarbon, the products are ALWAYS CO2 and H2O
General Formula is: C?H? + O2  CO2 + H2O
Example: C3H8 + O2  CO H2O