1. Types of Chemical Reactions
Identifying the Reactions Notes

2. Types of Chemical Reactions
Chemists classify chemical reactions into 5 main types
This helps to recognize patterns and predict the products
5 Types:
Synthesis
Decomposition
Combustion
Single Displacement
Double Displacement

3. Synthesis

4. Synthesis Reactions
Definition: Two or more substances react to form a single substance
SIMPLER substances combine to form one COMPLEX substance
General Equation: A + B  AB
To Identify: Has one product (a compound)
Example: 2 Ca + O2  2 CaO

5. Synthesis Examples Two elements react to form one compound.
2 Mg+ O2  2 MgO
Two compounds react to form one compound.
CaO + H2O  Ca(OH)2
One compound and an element react to form one compound.
2 SO2 + O2  2 SO3

6. Synthesis Analogy
It is like a relationship or marriage +

7. Decomposition

8. Decomposition Reactions
Definition: A single compound breaks down into two more simpler substances
The reverse of a synthesis reaction
General Equation: AB  A + B
To Identify: Has one reactant (a compound)
Example: H2CO3  H2O + CO2

9. Decomposition Examples
Metal carbonates produce metal oxides and carbon dioxide
Na2CO3-->Na2O + CO2
Metal hydroxides produce metal oxides and water
Ca(OH)2-->CaO + H2O
Metal chlorates produce metal chlorides and oxygen gas
KClO3-->KCl + O2
Oxyacids produce water and a nonmetal oxide gas
2HNO3-->H2O + N2O5
Metal oxides produce metals and oxygen gas
Au2O3--> O2 + Au
Water can produce oxygen gas and hydrogen gas
H2O--> H2 + O2

10. Decomposition Analogy
It is like a breakup or divorce +

11. Combustion

12. Combustion Reactions
Definition: A hydrocarbon reacts with oxygen to produce water and carbon dioxide
General Equation: CxHy +O2  CO2 + H2O
To Identify: O2 in reactants, CO2 and H2O in products
Example: CH4 + 2 O2  CO2 + 2 H2O

13. Single
Displacement

14. Single Displacement Reactions
Definition: One element replaces a second element in a compound
General Equation: A + BC  AC + B
To Identify: On each side of the equation, you will see one element and one compound
Example: Cu + 2AgNO3  Cu(NO3)2 + 2Ag

15. Single Displacement Examples
Types of SR Reactions
Metal replaces another metal
Mg + CuCl2  MgCl2 + Cu
Metal replaces hydrogen
2 Li + H2O  H2 + Li2O
Nonmetal replaces nonmetal
F2 + 2NaBr  2NaF + Br2

16. Single Displacement Reactions
Whether displacement will occur depends on reactivity of elements
Use activity series
The more reactive element can replace the less reactive element
If a less reactive element tries to replace a more reactive element then no reaction

17. Single Displacement Analogy
It is like getting divorced and finding a new spouse OR breaking up and finding a new girlfriend/boyfriend
Dancing analogy + +

18. Double
Displacement

19. Double Displacement Reactions
Definition: Involves an exchange of negative ions between two compounds
Often take place in aqueous solutions and produce a precipitate
A solid that is produced from liquid solution
General Equation: AB + CD  AD + CB
To Identify: On each side of the equation, you will see two compounds
Example: 2 NaOH + CuCl2  2 NaCl + Cu(OH)2

20. Double Displacement Analogy
Dancing with two couples and you switch partners

21. Reactions Summary Table
Type of Reaction
Reactants
Probable Products
Generic Equation
Synthesis
2 or more substances
One compound
A + B  AB
Decomposition
AB  A + B
Combustion
Hydrocarbon & oxygen
CO2 + H2O
CxHy + O2  CO2 + H2O
Single Replacement
Metal & compound
Nonmetal & compound
New compound & replaced metal
New compound & replaced nonmetal
A + BX  AX + B
Double Replacement
Two compounds
Two different compounds
AX + BY  AY + BX