Download Types of Chemical Reactions

Types of Chemical Reactions
Single Replacement Reactions
Double Replacement Reactions
Combustion Reactions
Recall
Synthesis Reactions
Two or more substances combine to form one
substance.
The general form is A + X AX
Decomposition Reactions
One substance reacts to form two or more
substances.
The general form is AX  A+X
Single Replacement Reactions
A metal will replace a metal ion in a
compound.
The general form is A + BX  AX + B
A nonmetal will replace a nonmetal ion
in a compound.
The general form is Y+BX  BY + X
Single Replacement Reactions
• Examples:
– Ni + AgNO3 NiNO3 + Ag
• Nickel replaces the metallic ion Ag+ (metal
replaces metal ion)
• The silver becomes free silver and the
nickel becomes the nickel (II) ion.
• Ni + AgNO3  Ag + Ni(NO3)2
–Balance the equation:
–Ni + 2AgNO3  2Ag + Ni(NO3)2
Thermite Reaction
• Steve Spangler Video Thermite
Thermite Reaction
• Al + Fe2O3 
• Aluminum will replace iron (III) as
was seen in the video.
• Iron (III) becomes Fe and aluminum
metal becomes Al3+.
• 2Al + Fe2O3  Al2O3 + 2Fe
Double Replacement Reactions
Ions of two compounds exchange places
with each other.
Reactants must be two ionic compounds,
in aqueous solution
The general form is AX+BY = AY + BX
Remember the Demonstration!!!!!!!!
Word - Lead (II) Nitrate + Potassium Iodide --> Potassium Nitrate + Lead
Iodide
Skeletal - Pb(NO3)2 (aq) + 2KI (aq) --> 2KNO3 (aq) + PbI2 (s)
What occurred???
This is a double displacement reaction
Double Replacement
NaOH + CuSO4 
The Na+ and Cu2+ switch places.
Na+ combines with SO42- to form Na2SO4.
Cu2+ combines with OH- to form Cu(OH)2
NaOH + CuSO4  Na2SO4 + Cu(OH)2
2NaOH + CuSO4  Na2SO4 + Cu(OH)2
Double Replacement
• CuSO4 + Na2CO3 
• Cu2+ combines with CO32- to form
CuCO3.
• Na+ combines with SO42- to form
Na2SO4.
• CuSO4 + Na2CO3  CuCO3 + Na2SO4
Double Replacement Reactions
• Think about it like “foil”ing in algebra, first and
last ions go together + inside ions go together
• Example:
AgNO3(aq) + NaCl(s)  AgCl(s) + NaNO3(aq)
• Another example:
K2SO4(aq) + Ba(NO3)2(aq)  2 KNO3(aq) + BaSO4(s)
Recognition
You need to be able to recognize which
reaction is taking place
Practice Examples:
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H2 + O2 
H2O 
Zn + H2SO4 
HgO 
KBr + Cl2 
• AgNO3 + NaCl 
• Mg(OH)2 + H2SO3 
 Synthesis
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Decomposition
Single Displacement
Decomposition
Single Displacement
Double Replacement
Double Replacement
Combustion Reactions
• Combustion means “add Oxygen”
Normally, a compound composed of
only C, H, (and maybe O) is reacted
with oxygen – usually called
“burning”
• If the combustion is complete, the
products will be CO2 and H2O.
• If the combustion is incomplete, , the
products will be CO (or possibly just
C) and H2O.
Combustion Reaction
When a substance combines with
oxygen, a combustion reaction results.
The combustion reaction may also be an
example of an earlier type such as 2Mg +
O2  2MgO.
The combustion reaction may be burning
of a fuel.
Combustion Reactions
• Combustion reactions involve light
and heat energy released.
• Natural gas, propane, gasoline, etc.
are burned to produce heat energy.
• Most of these organic reactions
produce water and carbon dioxide.
Combustion Reaction
When hydrocarbon compounds CxHx are
burned in oxygen, the products are water
and carbon dioxide.
CH4 + O2  CO2 + H2O
CH4 + 2O2  CO2 + 2H2O
Demonstration
Combustion Reactions
Generally combustion reactions involve the
burning of a Hydrocarbon (CxHx) in Oxygen.
Other elements can also burn with Oxygen
2Mg + O2  2MgO+ Energy
2H2 + O2  2H2O+ Energy (basis behind fuel cell
energy)
P4 + 5O2  P4O10 + Energy (matches)
Practice
Classify each of the following as to type:
H2 + Cl2  2HCl
Synthesis
Ca + 2H2O  Ca(OH)2 + H2
Single Displacement
Practice
2CO + O2  2CO2
Synthesis and Combustion
2KClO3  2KCl + 3O2
Decomposition
Practice
FeS + 2HCl  FeCl2 + H2S
Double Replacement
Zn + 2HCl  ? ZnCl2+ H2
Single Displacement