1. Types of Chemical Reactions

2. Synthesis Reaction
A + B A B
A + B  AB

3. Synthesis Reaction
A + B A B
A reaction where two
reactants combine to
make a larger, more
complex product

4. Synthesis Reaction
HCl(g) + NH3(g)  NH4Cl(s)

5. Decomposition Reaction
A B A + B
AB  A + B

6. Decomposition Reaction
A B A + B
A reaction where a more
complex molecule breaks
down to form two or more
simpler products

7. Decomposition Reaction
2NH4NO3(s)  4H2O(g) + 2N2(g) + O2(g) + energy
Timothy McVeigh bombing, 1995
Regular building demolition with ammonium
nitrate explosives

8. Decomposition Reaction
2KClO3(s) + energy  2KCl(s) + 3O2(g)

9. Single Displacement Reaction
A + B C A C + B
A + BC  AC + B

10. Single Displacement Reaction
A + B C A C + B
A reaction where an element
displaces another element in a
compound, producing a new
compound and a new element

11. Single Displacement Reaction
Hg(NO3)2(aq) + 2Ag(s)  Hg(s) + 2AgNO3(aq)

12. Single Displacement Reaction
2Na(s) + 2H2O(l)  2NaOH(aq) + H2(g)

13. Single Displacement Reaction
Hg(NO3)2(aq) + 2Ag(s)  Hg(s) + 2AgNO3(aq)
Will this reaction occur?
H2(g) + ZnCl2(aq)  2HCl(aq) + Zn(s)
What about this reaction?
The second reaction does not
occur. How will you know if a
single displacement reaction
will occur or not?

14. Single Displacement Reaction
The activity
series
(also on page
130, Table 4.2)
The “Who’s Hot
and Who’s Not
Analogy”

15. Single Displacement Reaction
MgSO4 + Zn  ?
Will this reaction occur?
This reaction will
not occur

16. Single Displacement Reaction
Involving halogens…
I2(aq) + CaBr2(aq)  ?
Will this reaction occur?
This reaction will not occur
REACTIVENESS
The position of
halogens in the periodic
table tells you how
reactive they are

17. Single Displacement Reaction
Involving halogens…
Cl2(g) + KBr(aq)  ?
Will this reaction occur?
REACTIVENESS
This reaction will occur
Cl2(g) + 2KBr(aq)  2KCl(aq) + Br2(l)

18. Double Displacement Reaction
A D + B C A C + B D
AD + BC  AC + BD

19. Double Displacement Reaction
A D + B C A C + B D
A reaction where elements in
different compounds exchange
places, producing two new
compounds

20. Double Displacement Reaction
Pb(NO3)2(aq) + 2KI(aq)  PbI2(s) + 2KNO3(aq)

21. Double Displacement Reaction
3CoCl2(aq) + 2Na3PO4(aq)  Co3(PO4)2(s) + 6NaCl(aq)
Will this reaction occur?
A reaction will
occur only if the
following will be
produced
1)Gas
2)Solid precipitate
3)Water Solubility
table

22. Double Displacement Reaction
3CoCl2(aq) + 2Na3PO4(aq)  Co3(PO4)2(s) + 6NaCl(aq)
Will this reaction occur? YES

23. Double Displacement Reaction
How will you know if the product is a gas?
CO2 is a gas, but not every gas is that simple to recognize
If one of the products is H2CO3(aq) or NH4OH(aq),
then you will get a gas!
H2CO3(aq)  H2O(l) + CO2(g)
NH4OH(aq)  NH3(g) + H2O(l)

24. Double Displacement Reaction
For example:
Na2CO3(aq) + 2HCl(aq)  2NaCl(aq) + H2CO3(aq)
H2CO3(aq)  H2O(l) + CO2(g)
The equation may be re-written as…
Na2CO3(aq) + 2HCl(aq)  2NaCl(aq) + H2O(l) + CO2(g)

25. Double Displacement Reaction
Neutralization reaction: Special type of
double displacement reaction
HCl(aq) + NaOH(aq)  H2O(l) + NaCl(aq)
Hydrochloric acid + sodium hydroxide  water + salt (sodium chloride)
Corrosive + corrosive  non-corrosive + non-corrosive

26. Double Displacement Reaction
Neutralization Reaction Example: Antacids neutralize
stomach acid
2HCl(aq) + CaCO3(aq)  CaCl2(aq) + H2CO3(aq)
H2CO3(aq)  H2O(l) + CO2(g)

27. Combustion Reaction
H 2O
fuel + O2 + CO2
A reaction of a fuel with oxygen,
producing energy in the form of
heat and/or light

28. Combustion Reaction
H2O
fuel + O2 + CO2

29. Combustion Reaction
Element + O2  “oxide” + energy
2Mg(s) + O2(g)  2MgO(s) + energy P4(s) + 5O2(g)  P4O10(g) + energy

30. Combustion Reaction
When burning a fuel, there are two types of
combustion to consider:
1st Type: COMPLETE COMBUSTION
Hydrocarbon + oxygen  carbon dioxide + water + energy
Ex. CH4(g) + 2O2(g)  CO2(g) + 2H2O(g) + energy

31. Combustion Reaction
2nd Type: INCOMPLETE COMBUSTION
Hydrocarbon + oxygen  carbon dioxide + water + carbon monoxide + carbon + energy
Ex. C4H10(g) + 5O2(g)  2CO2(g) + 5H2O(g) + CO(g) + C(s) + energy
POISONOUS!!!
BLACK!!!

32. Predicting the Products for a
Chemical Reaction
K + Cl2  ?
1) Are the reactants in their pure elemental form (i.e. O 2, Mg, Cl2)?
If yes, then this reaction is a SYNTHESIS REACTION
So there should only be ONE product, and it should contain
both reactants
2K + Cl2  2KCl

33. Predicting the Products for a
Chemical Reaction
H 2O  ?
2) Is there only ONE reactant?
If yes, then this reaction is a DECOMPOSITION REACTION
So there should be two products, each being a separate element
(i.e. Na, Ca, O2, I2, Br2) although that is not always the case
2H2O  2H2 + O2

34. Predicting the Products for a
Chemical Reaction
H 2 O2  ?
2) Is there only ONE reactant?
If yes, then this reaction is a DECOMPOSITION REACTION
So there should be two products, each being a separate element
(i.e. Na, Ca, O2, I2, Br2) although that is not always the case
2H2O2  2H2O + O2

35. Predicting the Products for a
Chemical Reaction
Zn + SnCl2  ?
3) If there are 2 reactants, is one of them a pure metal on its own?
If yes, then this reaction is a SINGLE DISPLACEMENT REACTION
So the metal that is on its own must take the place of the other
metal that is in the larger compound
Zn + SnCl2  ZnCl2 + Sn

36. Predicting the Products for a
Chemical Reaction
NaCl + AgNO3  ?
4) Are both of the reactants compounds?
If yes, then this reaction is a DOUBLE DISPLACEMENT REACTION
So the two metals must switch places with one another, forming
two new compounds
NaCl + AgNO3  NaNO3 + AgCl

37. Predicting the Products for a
Chemical Reaction
C8H18 + O2  ?
5) Is one of the reactants oxygen gas?
If yes, then this reaction is a COMBUSTION REACTION (as well as a
SYNTHESIS REACTION)
So the products must be an oxide and energy. If one of the
reactants is a hydrocarbon, then CO2 + H2O are the products.
2C8H18 + 25O2  16CO2 + 18H2O + energy