1. Chemical Equations Reactants Phase Notation Products Balanced
Li2CO Ba3(PO4)  Li3PO BaCO3
(aq) (aq) (aq) (s)
BASIC VOCABULARY;
Reactants Phase Notation
Products Balanced
Subscripts Yields ()
Coefficients

2. Everybody’s an expert!!
Find your partners by matching the lab equipment pictures on your grouping cards. Take your notebook with you. You will be in groups of 3 or 4.
Give each group member a number, 1-3 (or 4).
Read Chemistry: A Modern Course, pages with the following focus;
As you read, take notes on the distinguishing characteristics of each reaction classification and record an example reaction.
Spend 30 seconds explaining your classification to your partners. Be prepared to share with the class.
Groups of 3
Groups of 4
Student #1 – Single Displacement and Synthesis
Student #1 – Single Displacement and Combustion
Student #2 – Double Displacement and Synthesis
Student #2 – Double Displacement and Combustion
Student #3 –Decomposition and Combustion
Student #3 –Synthesis and Combustion
*************
Student #4 – Decomposition and Combustion

3. 5 Classifications of Equations 3 Types of Reactions
Expectations;
Recognition
Balancing
Predicting Products

4. 5 Classifications of Equations
Single displacement
Element + compound  compound + element
A + BC  B + AC
Mg HCl  MgCl2 + H2
3 CuSO Al  Al2(SO4) Cu

5. 5 Classifications of Equations
DOUBLE displacement
compound + compound  compound + compound
AB + CD  AD + CB
NaOH + HCl  NaCl + H2O
3 CuSO Al(OH)3  Al2(SO4) Cu(OH)2

6. 5 Classifications of Equations
SYNTHESIS
2 OR MORE SUBSTANCES  One compound
A + B  AB or a + BC  ABC
2 H2 + O2  2 H2O
NH3 + HCl  NH4Cl

7. 5 Classifications of Equations
Decomposition
ONE compound  2 or more substances
AB  A + b or abc  a + BC
2 KClO3  2 KCl + 3 O2
2 H2O2  2 H2O + O2

8. 5 Classifications of Equations
combustion
Hydrocarbon + oxygen carbon dioxide + water
___ + O2  CO2 + H2O
C5H O2  5 CO H2O
___C5H ___O2  ___CO2 + ___H2O

9. 5 Classifications of Reactions Which classification does this reaction fit?
1=single displacement 4=decomposition
2=double displacement 5=combustion
3=synthesis answer using frs
2 C4H O2  8 CO H2O
COMBUSTION

10. 5 Classifications of Equations Which classification does this reaction fit?
1=single displacement 4=decomposition
2=double displacement 5=combustion
3=synthesis answer using frs
4 P O2  2 P2O5
SYNTHESIS

11. 5 Classifications of Equations Which classification does this reaction fit?
1=single displacement 4=decomposition
2=double displacement 5=combustion
3=synthesis answer using frs
Cu2CO3 + Zn  ZnCO Cu
SINGLE DISPLACEMENT

12. 5 Classifications of Equations Which classification does this reaction fit?
1=single displacement 4=decomposition
2=double displacement 5=combustion
3=synthesis answer using frs
H2CO3  H2O + CO2
DECOMPOSITION

13. 2 KNO3+Zn(IO3)2 2 KIO3+Zn(NO3)2
5 Classifications of Equations Which classification does this reaction fit?
1=single displacement 4=decomposition
2=double displacement 5=combustion
3=synthesis answer using frs
2 KNO3+Zn(IO3)2 2 KIO3+Zn(NO3)2
Double displacement

14. 5 Classifications of Equations Which classification does this reaction fit?
1=single displacement 4=decomposition
2=double displacement 5=combustion
3=synthesis answer using frs
Cr + Fe2O3  CrO Fe
Single displacement

15. 5 Classifications of Equations Which classification does this reaction fit?
1=single displacement 4=decomposition
2=double displacement 5=combustion
3=synthesis answer using frs
CH O2  CO H2O
COMBUSTION

16. 5 Classifications of Equations Which classification does this reaction fit?
1=single displacement 4=decomposition
2=double displacement 5=combustion
3=synthesis answer using frs
KBr + H3PO4  K3PO4 + HBr
Double displacement

17. 5 Classifications of Equations Which classification does this reaction fit?
1=single displacement 4=decomposition
2=double displacement 5=combustion
3=synthesis answer using frs
8 Ba + S8  8 BaS
synthesis

18. 5 Classifications of Equations Which classification does this reaction fit?
1=single displacement 4=decomposition
2=double displacement 5=combustion
3=synthesis answer using frs
2 Ag2O  4 Ag + O2
decomposition

19. 5 Classifications of Equations Predict the products (or reconstruct the reactants)… THEN balance the equation
SYNthesis
Ag + O2
 Ag2O
4 Ag + O2  2 Ag2O

20. 5 Classifications of Equations Predict the products (or reconstruct the reactants)… THEN balance the equation
Double displacement
Li2CO3 + Al(NO3)3 ____ + _____
Li2CO3 + Al(NO3)3  LiNO3 + Al2(CO3)3
3 Li2CO3 + 2 Al(NO3)3  6 LiNO3 + Al2(CO3)3

21. 5 Classifications of Equations PERFECT practice makes perfect!
pp , #10-30 BLUE

22. Precipitation Acid-Base Oxidation-Reduction (a.k.a. REDOX)
3 Types of Reactions
Precipitation
Acid-Base
Oxidation-Reduction (a.k.a. REDOX)

23. 3 Types of Reactions Precipitation
Precipitate-solid formed by the reaction of two solutions.
A precipitation reaction is simply a reaction which forms a precipitate.
This happens when at least one of the products of a double displacement reaction happens to be insoluble…
…SOLUBILITY RULES

24. 3 Types of Reactions Precipitation
Write the equation for the precipitation reaction between potassium chromate & lead (II) nitrate.
Write the word equation
Write formulas
Balance equation
Identify the precipitate using the solubility rules

25. 3 Types of Reactions Precipitation
THREE FORMS OF THE EQUATION FOR A PRECIPITATION REACTION;
“Molecular” Equation
(the form of equation we are most familiar with)
Complete Ionic Equation
(shows dissolved substances in their dissociated form)
Net Ionic Equation
(shows only the species involved in the reaction. Eliminates spectator ions.)

26. 3 Types of Reactions Precipitation
3 forms of a precipitation reaction equation
1) “Molecular” Equation (“Normal”)
K2CrO4(aq) + Pb(NO3)2(aq)  2 KNO3(aq) + PbCrO4(s)
2)Complete Ionic Equation (all AQUEOUS substances are “dissociated”)
2K1+ + CrO42- + Pb NO31-  2K1+ + 2NO PbCrO4
3) Net Ionic Equation (eliminates spectator ions)
CrO42- + Pb2+  PbCrO4

27. Precipitation
Write the molecular, complete ionic and net ionic forms of the equation for the precipitation reaction between sodium phosphate and magnesium chloride.

28. 3 Types of Reactions Precipitation
Practice…
p. 246, #11, 13, 14.

29. 3 Types of Reactions Acid-Base Reactions
(a.k.a. neutralization)
Read World of Chemistry, p
and answer the following;
How do you recognize an acid by its formula?
How do you recognize a base by its formula?
What are the two products of a neutralization reaction?

30. 3 Types of Reactions Acid-Base Reactions
(a.k.a. neutralization)
ACID + BASE  WATER + “SALT”
(“Salt” – not just table salt, but includes any ionic compound that has
a cation other than H+ and an anion other than OH- or O2- .)
How do you recognize an acid by name? By formula?
How do you recognize a base by name? By formula?
ANS: formula starts with hydrogen
ANS: name ends in “acid”
ANS: name ends in “hydroxide”
(also ammonia & amines)
ANS: formula ends in hydroxide (OH-)
or contains nitrogen

31. 3 Types of Reactions Acid-Base Reactions
(a.k.a. neutralization)
Yeah, but what IS an acid? … What IS a base?
According to Svante Arrhenius…
…an acid produces hydrogen (H1+) ions in solution…
(This usually means that the compound contains an ionizable hydrogen atom…a hydrogen bonded to something with a high electronegativity, like oxygen, fluorine or chlorine)
…a base produces hydroxide (OH1-) in solution.
(The base either contains hydroxide, or makes it by ripping a hydrogen ion off of a water molecule.)

32. 3 Types of Reactions Acid-Base Reactions
(a.k.a. neutralization)
Yeah, but what IS an acid? … What IS a base?
According to Brönsted and Lowry…
…an acid is a PROTON (H+) DONOR…
…a base is a PROTON ACCEPTOR.

33. 3 Types of Reactions Acid-Base Reactions
(a.k.a. neutralization)
HINT for balancing neutralization reactions;
The underlying reaction in neutralization is;
H+ + OH-  H2O
In this reaction, ONE hydrogen ion reacts with ONE hydroxide ion to make ONE water molecule. If you match the number of hydrogen ions to the number of hydroxide ions and the number of water molecules, the rest of the equation typically takes care of itself!

34. 3 Types of Reactions Acid-Base Reactions
(a.k.a. neutralization)
HINT for balancing neutralization reactions;
Ex. Since phosphoric acid has 3 hydrogens and barium hydroxide has two hydroxides, we balance the equation by using a 2 for the acid to give 6 hydrogens and a 3 for the base to give 6 hydroxides. These would produce 6 water molecules.
___H3PO4 + ___Ba(OH)2  ___H2O + Ba3(PO4)2
_2_
_3_
_6_

35. 3 Types of Reactions Acid-Base Reactions
(a.k.a. neutralization)
p. 247, #22, 23.

36. 3 Types of Reactions Oxidation-Reduction Reactions
(a.k.a. REDOX)
Real-Life Redox

37. 3 Types of Reactions Oxidation-Reduction Reactions
(a.k.a. REDOX)
An element is oxidized when some of its electrons are “stolen”. We call this process “oxidation” because oxygen is the most common electron “thief”, but other elements can also be “oxidizers”.

38. 3 Types of Reactions Oxidation-Reduction Reactions
(a.k.a. REDOX)
The oxidation state of an element which “steals” electrons is reduced because it has acquired extra negatively charged particles (electrons).

39. 3 Types of Reactions Oxidation-Reduction Reactions
(a.k.a. REDOX)
Oxidation and reduction go hand in hand. Whenever one element is oxidized, the element that stole the electrons is reduced. You can never have one without the other!

40. 3 Types of Reactions Oxidation-Reduction Reactions
(a.k.a. REDOX)
Just remember…
SAYS L. E. O.
osing
lectrons is
xidation
G. E. R.
aining
lectrons is
eduction

41. Recognizing REDOX…
If ANY element changes its oxidation state, the reaction is a REDOX reaction.
If one element gains electrons, where does it get them from?
If one element loses electrons, where do they go?
REMEMBER that ALL ELEMENTS have an oxidation state of ZERO when they are alone (Not in a compound.)

42. Recognizing REDOX… Rules;
All elements have an oxidation state of zero when alone.
Elements in a compound have oxidation states which add up to zero. In polyatomic ions, the oxidation states of the elements add up to the charge on the ion.
Fluorine is -1.
Oxygen is -2. (Exception: in peroxides, oxygen is -1.)
Hydrogen is +1. (Exception: in metal hydrides, hydrogen is -1.)
For all Type I cations, the oxidation state is the same as their ionic charge. (Group I = +1, Group II = +2, Al = +3)

43. O2 NH3 SO42- BaCO3 O= N= S= Ba= H= O= C= O= Recognizing REDOX…
Assign oxidation states to each element…
O2 NH3 SO42- BaCO3
O= N= S= Ba=
H= O= C= O=

44. Cl2 CrF3 BrO31- KMnO4 Cl= Cr= Br= K= F= O= Mn= O= Recognizing REDOX…
Assign oxidation states to each element…
Cl2 CrF3 BrO31- KMnO4
Cl= Cr= Br= K=
F= O= Mn= O=

45. Recognizing REDOX…
The reactant which contains the element which gets oxidized is called the reducing agent. The reactant which contains the element which gets reduced is called the oxidizing agent.

46. 2 C3H6 + 9 O2  6 CO2 + 6H2O Recognizing REDOX… Identify…
a)…the element which is reduced.
b)…the element which is oxidized.
c)…the oxidizing agent.
d)…the reducing agent.

47. N2 + 3 H2  2 NH3 Recognizing REDOX… Identify…
a)…the element which is reduced.
b)…the element which is oxidized.
c)…the oxidizing agent.
d)…the reducing agent.

48. 2 KClO3  2 KCl + 3O2 Recognizing REDOX… Identify…
a)…the element which is reduced.
b)…the element which is oxidized.
c)…the oxidizing agent.
d)…the reducing agent.

49. 2 Na3PO4 + 3 NiCl2  6 NaCl + Ni3(PO4)2
Recognizing REDOX…
2 Na3PO4 + 3 NiCl2  6 NaCl + Ni3(PO4)2
Identify…
a)…the element which is reduced.
b)…the element which is oxidized.
c)…the oxidizing agent.
d)…the reducing agent.

50. In Summary Recognizing REDOX…
Single Displacement is (Never Sometimes Always) REDOX.
Double Displacement is (Never Sometimes Always) REDOX.
Synthesis is (Never Sometimes Always) REDOX.
Decomposition is (Never Sometimes Always) REDOX.
Combustion is (Never Sometimes Always) REDOX.

51. Writing Chemical Equations
pp , #9-30 (Write and balance)
pp , (Variety)
pp , (Redox) #1-21
pick particularly perplexing problems!