1. IPS Unit 12 Chemical Equations Section 2

2. Types of Reactions Unit 12 – Section 2: Types of Reactions
There are five types of chemical reactions:
Combustion Reaction
Synthesis Reaction [Composition]
Decomposition Reaction
Single-Displacement Reaction [Single-Replacement]
Double-Displacement Reaction [Double-Replacement]

3. Combustion Reaction Unit 12 – Section 2: Types of Reactions
- Occurs when a hydrocarbon reacts with oxygen gas.
If you have observed something burning, you have observed a combustion reaction
In order to burn, you need the 3 items of the “fire triangle”:
A fuel (hydrocarbon)
Oxygen
Something to ignite the reaction (spark)

4. Combustion Reaction (Cont)
Unit 12 – Section 2: Types of Reactions
Combustion Reaction (Cont)
hydrocarbon + oxygen  carbon dioxide + water
The products in combustion are ALWAYS carbon dioxide and water. (Although incomplete burning does cause some by-products like carbon monoxide.)
Combustion is used to heat homes and run automobiles (octane, as in gasoline, is C8H18)

5. reactant + reactant  1 product
Unit 12 – Section 2: Types of Reactions
Synthesis (Composition) Reaction
occurs when two substances (generally elements) combine and form one compound.
reactant + reactant  1 product
A + X  AX
Examples:
2H2 + O2  2H2O
C + O2  CO2

6. 1 reactant  product + product
Unit 12 – Section 2: Types of Reactions
Decomposition Reaction
occurs when one compound breaks up into the elements or to simpler compounds
1 reactant  product + product
AX  A + X
Examples:
2H2O  2H2 + O2
2HgO  2Hg + O2

7. Single-Displacement Reaction (Single-Replacement)
Unit 12 – Section 2: Types of Reactions
Single-Displacement Reaction (Single-Replacement)
occurs when one element replaces another in a compound
A + BX → AX + B
Y + BX → BY + X
Examples:
NaCl + F2  NaF + Cl2
Zn + HCl  ZnCl2 + H2

8. compound + compound  product + product
Unit 12 – Section 2: Types of Reactions
Double-Displacement Reaction (Double-Replacement)
occurs when a metal replaces a metal in a compound and a nonmetal replaces a nonmetal in a compound
compound + compound  product + product
AX + BY  AY + BX

9. Double-Displacement Reaction (Double-Replacement)
Unit 12 – Section 2: Types of Reactions
Double-Displacement Reaction (Double-Replacement)
-Think about it like “foiling” in algebra, first and last ions go together + inside ions go together
Examples:
AgNO3 + NaCl  AgCl + NaNO3
K2SO4 + Ba(NO3)2  KNO3 + BaSO4

10. Practice Unit 12 – Section 2: Types of Reactions 2 9 6 6
Predict the products, balance the reactions, and state the types of reactions:
 Double-Displacement
BaCl2 + H2SO4 
C6H O2 
Zn + CuSO4 
Ca + Br2 
CaCO3  2
HCl + BaSO4
 Combustion
CO2 + H2O
 Single-Displacement
Cu + ZnSO4
CaBr2
 Synthesis
 Decomposition
CaO + CO2