2. change from the original substances.
 Chemical Change – alters the materials composition making a new substance with new properties.
 Clues that a chemical change has occurred:
A release of energy—heat, light, & sound
Change in temperature—hot or cold
Formation of bubbles or solids in a liquid
Change in color or odor—only if there is a
change from the original substances.

3.  Chemical Change Example—an insoluble solid forms when 2 liquids are combined (precipitate).

4. Synthesis or Combination Decomposition Combustion Single Replacement
 By learning what these reactions look like and following the pattern of these reactions, you can predict the products.
 5 Types of Reactions
Synthesis or Combination
Decomposition
Combustion
Single Replacement
Double Replacement

5. Combination or Synthesis
In a combination reaction, two or more
elements combine to form a single compound.
A + B + C ABC
Only one PRODUCT…
Example #1: Mg S
MgS + Mg S

6. Combination or Synthesis
Example #2:
2 Fe + 3 S
Fe2S3
Only one PRODUCT… S Fe S Fe S

7. Combination/Synthesis Examples
3 Ca + N2 →
Ca3N2
4 K + O2 → 2 K2O
Only one PRODUCT…

8. Decomposition ABC → A + B + C ABC → AB + C Example #1:
In a decomposition reaction, 1 larger compound decomposes or breaks apart into 2 or more separate smaller compounds.
ABC → A + B + C
ABC → AB + C
Only one REACTANT…
Example #1:
2 H2O2 2 H2O + O2
H O O H
O O H H

9. Decomposition Examples
Only one REACTANT…
2 PO3 2 P + 3 O2
2 AlN 2 Al + N2
Mn2S3
2 Mn + 3 S

10. Combustion Reactions AB + Example #1 O2 → AO + BO CH4 + 2 O2
In a combustion reaction the elements of a compound react with Oxygen. The complete combustion of a hydrocarbon always produces CO2 and H2O.
AB +
Example #1
O2 → AO + BO
CH4 + 2 O2
H O O
O O
CO2 + 2 H2O H
C H H

11. Combustion Reactions C10H8 + 12 O2 → 10 CO2 + 4 H2O
Example #2
C2H5OH + 3 O2 2 CO2 + 3 H2O
Example #3
C10H O2 → 10 CO2 + 4 H2O
CO2 and H2O are products!

12. Single Replacement Reactions
•In a single replacement reaction, a single element replaces a second element that is part of an IONIC compound (Switch places).
•Metal replaces Metal (+)
•Non-metal replaces Non-metal (-)
•Free element must be more active for
replacement to occur. (Activity Series)
Element + Compound → Element + Compound

13. Single Replacement Reactions
A + BC
D + BC
Example #1:
B + AC
C + BD
2 Na Na +
2 HCl H2
+ 2 NaCl Cl H Na
H Cl
Element + Compound → Element + Compound

14. Single Replacement ExamplesH2
+ ZnCl2 Zn
2 HCl +
Example #3:
2 Al + 3 MgO
3 Mg + Al2O3
Element + Compound → Element + Compound

15. Double Replacement Reactions
•In a Double replacement reaction, two elements in two different compounds switch places. (Metal replaces metal.)
AB + CD CB + AD
Compound + Compound → Compound + Compound
Example #1:
NaCl + KBr KCl + NaBr
Na Cl
K Br

16. Double Replacement Examples
2 AlCl3
+ 3 MgO
Al2O3 +
3 MgCl2
Example #3:
Li2O +
FeCl2
2 LiCl
+ FeO
Example #4:
Ca(OH)2 + H3PO4 → Ca3(PO4)2 + H2O
Compound + Compound → Compound + Compound

17. +
DECOMPOSITION

18.  N2 + O2 → N2O
Synthesis

19.  NaBr + Cl2 →
NaCl + Br2
Single
Replacement

20.  BaCl2 + (NH4)2SO4 →
BaSO4 +
NH4Cl
Double
Replacement

21.  CO →
C + O2
Decomposition

22. Mg + ZnSO4 → Zn + MgSO4
Single
Replacement

23.  NaCl + AgNO3 → NaNO3
+ AgCl
Double
Replacement

24. C6H12O6 +
O2 → H2O + CO2
Combustion

25. CaCO3
→ CaO + CO2
Decomposition

26.  Label each tab as the picture below:
TYPES OF
CHEMICAL REACTIONS
Synthesis
Decomposition
Combustion
Single Replacement
Double Displacement
Double Displacement
SYNTHESIS/ADDITION
DECOMPOSITION
Single Displacement
Combustion

27. 1. Definition of each type from the
 On each flap record the following:
1. Definition of each type from the
notes.
A way to recognize pattern
(ex: 1 product)
1 “real” example of this type of
reaction (ex: Na +
Cl2 → NaCl)