1. Types of Reactions You need to be able to identify each type.
Synthesis reactions
Decomposition reactions
Single displacement reactions
Double displacement reactions
Combustion reactions
You need to be able to identify each type.

2. 1. Synthesis
Example C + O2 O C +  O C
General: A + B  AB

3. Ex. Synthesis Reaction

4. Practice Predict the products. Na(s) + Cl2(g)  Mg(s) + F2(g) 
Al(s) + F2(g)  2 2
NaCl(s)
MgF2(s) 2 3 2
AlF3(s)
Now, balance them.

5. 2. Decomposition
Example: NaCl  Cl Na Cl + Na
General: AB  A + B

6. Ex. Decomposition Reaction

7. Went from neutral (0) to (+2) Went from (+2) to Neutral (0)
3. Single Displacement
Example: Zn + CuCl2
Zn was oxidized
Went from neutral (0) to (+2)  Zn Cl Cu + Cl Zn Cu +
Cu was reduced
Went from (+2) to Neutral (0)
General: AB + C  AC + B

8. Ex. Single Replacement Reaction

9. Single Replacement Reactions
Write and balance the following single replacement reaction equation:
Zn(s) HCl(aq)  ZnCl2 + H2(g) 2
NaCl(s) + F2(g)  NaF(s) + Cl2(g)
Al(s)+ Cu(NO3)2(aq) 2 2 2 3 3
Cu(s)+ Al(NO3)3(aq) 2

10. 4. Double displacement General: AB + CD  AD + CB Example: MgO + CaS 

11. 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)  KNO3(aq) + BaSO4(s) 2

12. 5. Combustion Reactions
Combustion reactions - a hydrocarbon reacts with oxygen gas.
This is also called burning!!!
In order to burn something you need the 3 things in the “fire triangle”:
1) Fuel (hydrocarbon) 2) Oxygen 3) Something to ignite the reaction (spark)

13. Combustion Reactions In general: CxHy + O2  CO2 + H2O
Products 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)

14. Combustion
Example
C5H O2  CO2 + H2O
Write the products and balance the following combustion reaction:
C10H O2  8 5 6

15. Endothermic & Exothermic Change

16. Whenever chemical reactions occur, energy is transferred to or from the surroundings.
An exothermic reaction is one which transfers heat energy to the surroundings
An endothermic reaction is one which takes heat energy from the surroundings

17. Exothermic process: a physical or chemical change that releases heat energy
reaction
Exothermic Change - heat is given off and the temperature rises
Burning fossil fuels is an exothermic reaction.

18. Reactants  Products + Energy as Heat

19. Exothermic Examples Chemical Change Physical Change A candle flame
Rusting iron
Burning sugar
Glow sticks
Fire crackers
Physical Change
Some hand warmers
Some dissolving

21. Endothermic reaction - heat is taken in and the temperature may drop
Endothermic process: a physical or chemical change that requires (or absorbs) heat energy
reaction
Endothermic reaction - heat is taken in and the temperature may drop
Photosynthesis is an endothermic reaction (requires energy input from sun)

22. Reactants + Energy as Heat  Products

23. Endothermic Examples Chemical Change Physical Change Baking bread
Cooking an egg
Physical Change
Sometimes dissolving
Cold packs from nurse