1. Classifying chemical reactions
Why?
When we classify, we are able to organize information and understand the material better.

2. Quick review: Symbolizing chemical reactions
coefficients
reactants
products

3. 5 Classes of Chemical Reactions
Synthesis:
Decomposition:
Single replacement:
Double replacement:
Combustion:
To make
To break down
Single Substitute
Two substitutes
To burn

4. 1. Synthesis Reactions A + B  AB
How do we recognize a synthesis reaction?
a. A single product forms from two or more reactants.
Example:
__ Mg + __ O2  __ MgO
General format: 2 2
A + B  AB

5. How does this cartoon symbolize a synthesis reaction?AB
Indicate which letter each animal represents.

6. Synthesis reaction demonstration

7. 2. Decomposition Reaction
How do we recognize a decomposition reaction?
a. A reactant breaks down into two or more products
Example:
H2O2 H2O + O2
General Format:
AB  A + B

8. How does this cartoon symbolize a decomposition reaction?AB A B
Indicate which letter each figure represents.

9. Decomposition example __NaCl  __ Na + __Cl2

10. 3. Single Replacement Reactions
How do we recognize a single replacement reaction?
a. A single element reacts with a compound
b. Products are a different single element and a different compound
Example:
__ Zn + __ HCl ---> __ ZnCl2 + __ H2
General format:
A + BC  AC +B 2

11. How does this cartoon symbolize a single replacement reaction?BC
Indicate which letter each figure represents.

12. Single replacement reaction example

13. 4. Double Replacement Reaction
How do we recognize a double replacement reaction?
a. Two compounds exchange partners and form two new compounds
b. This reaction often produces a precipitate
Example:
__ FeS + __ HCl ---> __ FeCl2 + __ H2S
General format:
AB + CD  AD + CB 2

14. How does this cartoon symbolize a double replacement reaction?
Indicate which letter each figure represents.

15. Example of a double replacement reaction

16. 5. Combustion Reactions How do we recognize a combustion reaction?
a. A compound containing CHO reacts with oxygen
b. Products are carbon dioxide and water
Example (combustion of ethanol):
__ CH3CH2OH + __ O2  __ CO2 +__ H2O
General format: 1 3 2 3
CHO + O2  CO2 + H2O

17. Example of a combustion reaction