Drill: Calculate the solubility of
PbSO4
Ksp = 2.0 x 10-14
Oxidation Reduction Reactions(REDOX)
REDOX Reactions
•Chemical reactions in which electrons
are transferred
Oxidation•The act of losing
electrons
•Oxidation number increases
Reduction•The act of gaining
electrons
•Oxidation number decreases
REDOX Fact•You cannot have oxidation without
reduction or reduction without oxidation
Oxidizing Agent•A substance that oxidizes another
•The oxidizing agent will be reduced
Reducing Agent•A substance that
reduces another
•The reducing agent will be oxidized
Determine elements being: oxidized & reduced
__ MnO4-1 + __ NH3
__ MnO2 + __ NO2-1
Drill: determine ox # of each element:
__MnO4-1 + __Fe
__Mn2O3 + __Fe+2
Balancing REDOX Reactions
Balancing Redox Rxns1)Determine all ox #
2)Determine elements being oxidized & reduced
3)Divide rxn into half-rxns
4)Balance half-rxns
Balancing Half-Rxnsa)Balance redox elements
b)Balance ox # with e-
c)Balance e- between the two half-rxns
Balancing Half-Rxnsd)Balance total charge
with H+ or OH-
e)Balance H’s with waterf) Check balance with oxygen
Balancing Redox Rxns5) Add the two half-reactions
a)Cancel like substances from each side of the full reaction
b)Check work
Balance Redox Rxns:
MnO2 + Cl-1
Mn+2 + Cl2
in acid
AP CHM HW•Read: Chapter 4.3
•Problem: 40
•Page: 108
CHM II HW•Read: Chapter 4.5
•Problem: 45
•Page: 170
Balance Redox Rxns:
Cr2O7-2 + NH3
Cr+3 + NO3-1
in base
Drill: Balance: MnO4
-1 + N2O3
Mn+3 + N2O5
in base
Drill: Balance Rxns:
HNO3 + Cu
N2O + Cu+2
Balance Redox Rxns:
SO2 + Pb(OH)2
SO3 + Pb
in base
Balance Redox Rxns:
MnO2 + P4
Mn2O7 + PH3
in acid
AP CHM HW•Read: Chapter 4.3
•Problems: 41
•Page: 108
CHM II HW•Read: Chapter 21
•Problems: 3
•Page: 893
Balance Redox Rxns:
FeCl2 + KNO3
FeCl3 + KNO
in base
Balance Redox Rxns:
SnF2 + KIO4
KI + SnF4
in acid
Balance Redox Rxns:
IO3-1 + I-1
I3-1
in acid
Balance Redox Rxns:
PbBr4 + K2O
PbBr2 + O2
in acid
Balance Redox Rxns:
Ca + VO4-3
CaO + V+2
in acid
Balance Redox Rxns:
Fe(OH)3 + Cr(OH)4-1
Fe(OH)2 + CrO4-2
Balance Redox Rxns:
Ni(OH)2 + N2H4
Ni + N2
in base
Balance Redox Rxns:
K3PO4 + Cr+2
P2O3 + K2CrO3
in acid
Balance Redox Rxns:
H2SO4 + Cr+2
SO + H2Cr2O7
in acid
Balance Redox Rxns:
PH3 + KMnO4
P2O5 + Mn2O3
in KOH