1. 2Al + 3Br2  2AlBr3

2. Standard: Identify the reactants, products, and types of different chemical reactions: composition, decomposition, double replacement, single replacement, combustion.
Objective: Classify a chemical reaction as composition, decomposition, single replacement, double replacement, and combustion.

3. Chemical Reactions

4. Types of Reactions
There are five types of chemical reactions we will talk about:
Composition reactions (synthesis)
Decomposition reactions
Single replacement reactions
Double replacement reactions
Combustion reactions
You need to be able to identify the type of reaction

5. Types of Reactions Basically: A + B  AB Example: 2H2 + O2  2H2O
Composition reactions (synthesis) - occurs when two substances (generally elements) combine and form a compound.
reactant + reactant  1 product
Basically: A + B  AB
Example: 2H2 + O2  2H2O
Example: C + O2  CO2

6. 2. Decomposition Reactions
Decomposition reactions - occurs when a compound breaks up into the elements.
1 Reactant  Product + Product
In general: AB  A + B
Example: 2 H2O  2H2 + O2
Example: 2 HgO  2Hg + O2

7. 3. Single Replacement Reactions
Single Replacement Reactions - occurs when one element replaces another in a compound.
A metal can replace a metal (+) OR a nonmetal can replace a nonmetal (-).
element + compound  product + product
A + BC  AC + B (if A is a metal) OR
A + BC  BA + C (if A is a nonmetal)
(remember the cation always goes first!)

8. 4. Double Replacement Reactions
Double Replacement Reactions - occurs when a metal replaces a metal in a compound or a nonmetal replaces a nonmetal in a compound
Compound + compound  product + product
AB + CD  AD + CB (metals are blue, non-metals are red)
Example:
LiCl + Na2O  Li2O + NaCl

9. 5. Combustion Reactions
Combustion reactions occur when 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) A Fuel (hydrocarbon) 2) Oxygen to burn it with 3) Something to ignite the reaction (spark)

10. Combustion Reactions In general: CxHy + O2  CO2 + H2O
Products in combustion 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)

11. H2 + Cl2  HCl

12. KI + Br2  KBr + I2

13. Mg + O2  MgO

14. H2CO3  CO2 + H2O

15. AgNO3 + NaCl  AgCl + NaNO3

16. Li + H2O  LiOH + H2

17. CH4 + O2  CO2 + H2O

18. FeS + HCl  FeCl2 + H2S

19. KClO3  KCl + O2

20. Zn + HCl  ZnCl2 + H2

21. Mg(NO3)2 + KOH  Mg(OH)2 + KNO3

22. C3H8 + O2  CO2 + H2O

23. Identify the Type of Reaction
Na(s) + Cl2 (g)  NaCl (s)
K (s) + Cl2 (g)  KCl (s)
PbO2 (s)  Pb (s) + O2 (g)
Fe2O3 (s) + Al (s)  Al2O3 (s) + Fe (s)
C2H2 (g) + O2 (g)  CO2 (g) + H2O (l)
Ba3N + K2S  BaS + K3N

24. Identify the Type of Reaction
Exit Slip- Identify the types of reactions
Ca(s) + Cl2 (g)  CaCl2 (s)
HCl (aq) + Na (s)  H2(g) + NaCl (aq)

25. Identify the Type of Reaction
HOMEWORK: page 284 #1-2

26. Steps to Writing Reactions
Some steps for writing reactions
Identify the type of reaction
Predict the product(s) using the type of reaction as a model (DON’T FORGET TO CROSS THE CHARGES).
Balance it
Don’t forget about the diatomic elements! (BrINClHOF) For example, Oxygen is O2 as an element.

27. Synthesis Practice
Predict the products. Write and balance the following synthesis reaction equations.
Sodium metal reacts with chlorine gas
Na(s) + Cl2(g) 
Solid Magnesium reacts with fluorine gas
Mg(s) + F2(g) 
Aluminum metal reacts with fluorine gas
Al(s) + F2(g) 

28. Decomposition Exceptions
Carbonates and chlorates are special case decomposition reactions that do not go to the elements.
Carbonates (CO32-) decompose to carbon dioxide and a metal oxide
Example: CaCO3  CO2 + CaO
Chlorates (ClO3-) decompose to oxygen gas and a metal chloride
Example: 2 Al(ClO3)3  2 AlCl3 + 9 O2

29. Decomposition Practice
Predict the products. Then, write and balance the following decomposition reaction equations:
Solid potassium chlorate decomposes KClO3(s) 
Aluminum nitride decomposes
AlN(s) 

30. BaCO3(s)  Co(s) (III) + S(s)  NI3(s)  Practice
Identify the type of reaction for each of the following synthesis or decomposition reactions, and write the balanced equation:
BaCO3(s) 
Co(s) (III) + S(s) 
NI3(s) 

31. Homework ___ NaBr + ___ H3PO4  ___ Na3PO4 + ___ HBr
Identify the type of reaction for each of the following and balanced
___ NaBr + ___ H3PO4  ___ Na3PO4 + ___ HBr
__ Ca(OH)2 + __ Al2(SO4)3  __ CaSO4 + __ Al(OH)3
____ Mg + ____ Fe2O3  ____ Fe + ____ MgO
____ C2H4 + ____ O2  ____ CO2 + ____ H2O
___ H2 + ___ O2  ____ H2O
___ Ca + ____ O2  ____ CaO
____ KCl  ____ K + ____ Cl2

32. Homework
Identify the reaction type, predict the products and balance. NaClO3  Li + N2  BaO  Fe (III) + Cl 

33. Single Replacement Reactions
Write and balance the following single replacement reaction equation:
Zinc metal reacts with aqueous hydrochloric acid
Zn(s) (II) + HCl(aq) 
Note: Zinc replaces the hydrogen ion in the reaction

34. Single Replacement Reactions
Sodium chloride solid reacts with fluorine gas
NaCl(s) + F2(g) 
Note that fluorine replaces chlorine in the compound
Aluminum metal reacts with aqueous copper (II) nitrate
Al(s)+ Cu(NO3)2(aq)

35. Double Replacement Reactions
Example:
AgNO3(aq) + NaCl(s) 
Another example:
K2SO4(aq) + Ba(NO3)2(aq)  2

36. Practice HCl(aq) + AgNO3(aq)  Pb(NO3)2(aq) + BaCl2(aq) 
Predict the products. Balance the equation
HCl(aq) + AgNO3(aq) 
Pb(NO3)2(aq) + BaCl2(aq) 
FeCl3(aq) + Na(s) 
CaCl2(aq) + Na3PO4(aq) 
K(s) + CuSO4(aq) 

37. Combustion
Example
C5H O2  CO2 + H2O
Write the products and balance the following combustion reaction:
C10H O2 

38. Mixed Practice
State the type, predict the products, and balance the following reactions:
BaCl2 + H2SO4 
C6H12 + O2 
Zn + CuSO4 
Cs + Br2 
FeCO3 

39. Exit Slip Predict products, identify type of reaction, and balance
Mg HNO3 