Types of Chemical
Reactions
Types of Chemical Reactions

The six types of chemical reactions you
need to know are:
Types of Chemical Reactions

The six types of chemical reactions you
need to know are:
1. Synthesis
2. Decomposition
3. Single Replacement
4. Double Replacement
5. Acid-Base Neutralization
6. Combustion
1. Synthesis Reaction
1. Synthesis Reaction

When two or more substances
combine to form one substance.
 The
general form is:
A + X  AX
1. Synthesis Reaction

Examples:
1. Synthesis Reaction

Examples:
 2Mg + O2  2MgO
1. Synthesis Reaction

Examples:
 2Mg + O2  2MgO
 SO2 + H2O  H2SO3
1. Synthesis Reaction

Examples:
 2Mg + O2  2MgO
 SO2 + H2O  H2SO3
 BaO + H2O  Ba(OH)2
1. Synthesis Reaction

Examples:
 2Mg + O2  2MgO
 SO2 + H2O  H2SO3
 BaO + H2O  Ba(OH)2
 Na2O + CO2  Na2CO3
1. Synthesis Reaction

Examples:
 2Mg + O2  2MgO
 SO2 + H2O  H2SO3
 BaO + H2O  Ba(OH)2
 Na2O + CO2  Na2CO3
 CaO + SO2  CaSO3
1. Synthesis Reaction

Synthesis reactions may also be called
composition or combination reactions.
1. Synthesis Reaction

In all cases, two or more reactants
combine to form a single product.
1. Synthesis Reaction

In all cases, two or more reactants
combine to form a single product.
A + X  AX
2. Decomposition Reactions
2. Decomposition Reactions

When one substance reacts to form
two or more substances.
 The
general form is:
AX  A + X
2. Decomposition Reactions

Examples:
2. Decomposition Reactions

Examples:
 2H2O
 2H2 + O2
2. Decomposition Reactions

Examples:
 2H2O
 2H2 + O2
 CaCO3  CaO + CO2
2. Decomposition Reactions

Examples:
 2H2O
 2H2 + O2
 CaCO3  CaO + CO2
 H2CO3  H2O + CO2
2. Decomposition Reactions

Examples:
 2H2O
 2H2 + O2
 CaCO3  CaO + CO2
 H2CO3  H2O + CO2
 Ca(OH)2  CaO + H2O
2. Decomposition Reactions
 Decomposition
reactions are the
reverse of synthesis reactions.
3. Single Replacement Reactions
3. Single Replacement Reactions

A metal will replace a metal ion in a
compound.

The general form is
A + BX  AX + B
3. Single Replacement Reactions

A nonmetal will replace a nonmetal
ion in a compound.

The general form is
Y + BX  BY + X
3. Single Replacement Reactions

Examples:
3. Single Replacement Reactions

Examples:
 Ni + AgNO3 
3. Single Replacement Reactions

Examples:
 Ni + AgNO3 
 Nickel replaces the metallic ion Ag+.
3. Single Replacement Reactions

Examples:
 Ni + AgNO3 
 Nickel replaces the metallic ion Ag+.
 The silver becomes free silver and the
nickel becomes the nickel(II) ion.
3. Single Replacement Reactions

Examples:
 Ni + AgNO3 
 Nickel replaces the metallic ion Ag+.
 The silver becomes free silver and the
nickel becomes the nickel(II) ion.
 Ni + AgNO3  Ag + Ni(NO3)
4. Double Replacement
Reactions
4. Double Replacement
Reactions

When ions of two compounds
exchange places with each other.
4. Double Replacement
Reactions

When ions of two compounds
exchange places with each other.
 The
general form is:
AX + BY  AY + BX
4. Double Replacement
Reactions

For Example:

NaOH + CuSO4 
4. Double Replacement
Reactions





For Example:
NaOH + CuSO4 
The Na+ and Cu2+ switch places.
Na+ combines with SO42- to form Na2SO4.
Cu2+ combines with OH- to form Cu(OH)2
4. Double Replacement
Reactions

NaOH + CuSO4  Na2SO4 + Cu(OH)2
4. Double Replacement
Reactions

NaOH + CuSO4  Na2SO4 + Cu(OH)2

2NaOH + CuSO4  Na2SO4 + Cu(OH)2
4. Double Replacement
Reactions
For Example:
 CuSO4 + Na2CO3  ?? + ??
 Cu2+ combines with CO32- to form
CuCO3.
 Na+ combines with SO42- to form
Na2SO4.

4. Double Replacement
Reactions

CuSO4 + Na2CO3  CuCO3 + Na2SO4
5. Acid-Base Neutralization
5. Acid-Base Neutralization

When an acid and a base react to form a
salt and water.
5. Acid-Base Neutralization


When an acid and a base react to form a
salt and water.
The basic form is:
HX + MOH > MX + H2O
Acid + Base > Salt + Water
5. Acid-Base Neutralization
Acids usually have an H on the left.
Examples:

HCL – Hydrochloric Acid (hydrogen chloride)
HNO3 – Nitric Acid (hydrogen nitrate)
H2SO4 – Sulphuric Acid (hydrogen sulphate)
H3PO4 – Phosphoric Acid (hydrogen phosphate)
5. Acid-Base Neutralization
Bases have an OH- on the right side.
Examples:

NaOH – Sodium hydroxide
Mg(OH)2 – Magnesium hydroxide
NH4OH – Ammonium hydroxide
5. Acid-Base Neutralization

Example:
HCl + NaOH > NaCl + H2O
Acid + Base
> Salt + Water
6. Combustion Reaction
6. Combustion Reaction

When a compound or element reacts with
oxygen to form an oxide and produce
heat.
6. Combustion Reaction
When a compound or element reacts with
oxygen to form an oxide and produce
heat.
Example:

6. Combustion Reaction
When a compound or element reacts with
oxygen to form an oxide and produce
heat.
Example:

CH4 + O2 > CO2 + H2O
6. Combustion Reaction

Combustion reactions always have
O2 as a reactant, and CO2 as a
product.
Now, to sum it all up…
Practice

Classify each of the following as to
type:
Practice


Classify each of the following as to
type:
H2 + Cl2  2HCl
Practice


Classify each of the following as to
type:
H2 + Cl2  2HCl

Synthesis
Practice


Classify each of the following as to
type:
H2 + Cl2  2HCl


Synthesis
Ca + 2H2O  Ca(OH)2 + H2
Practice


Classify each of the following as to
type:
H2 + Cl2  2HCl


Synthesis
Ca + 2H2O  Ca(OH)2 + H2

Single replacement
Practice

2CO + O2  2CO2

2KClO3  2KCl + 3O2
Practice

2CO + O2  2CO2


Synthesis
2KClO3  2KCl + 3O2
Practice

2CO + O2  2CO2


Synthesis
2KClO3  2KCl + 3O2

Decomposition
Practice

FeS + 2HCl  FeCl2 + H2S

Zn + HCl  ? + ?
Practice

FeS + 2HCl  FeCl2 + H2S


Double replacement
Zn + HCl  ? + ?
Practice

FeS + 2HCl  FeCl2 + H2S


Double replacement
Zn + HCl  ? + ?

Single replacement
Practice

FeS + 2HCl  FeCl2 + H2S


Double replacement
Zn + HCl  ? + ?
Single replacement
 Zn + 2HCl  ZnCl2 + H2
