Unit 5. ELECTROCHEMISTRY. REDOX REACTIONS. OXIDATION: _____________________ REDUCTION: ____________________ REDOX: _____________________________. EXAMPLE. SHOW, WITH ARROWS, THE LOSS AND GAINS OF ELECTRONS. OXIDIZING AGENT: ___________________ REDUCING AGENT: ____________________
SHOW, WITH ARROWS, THE LOSS AND GAINS OF ELECTRONS
REDUCING AGENT: ____________________
PRACTICE PROBLEMS, PAGE 467, #1-4
Is this a proper half reaction?
A single element undergoes both oxidation and reduction in the same reaction.
Practice Problems, 5-8
We have seen net ionic equations with monatomic elements (Cu, Zn) and single-element ions.
We used ionic charges to describe the transfer of electrons.
Many reactions involve reactants or products with covalent bonds cannot use ionic charges to describe the transfer of electrons.
Oxidation numbers: actual/hypothetical charges, assigned using a set of rules.
Molecules with Atoms of Different Electronegativity
Oxidation # of:
H: +1 except when with metal hydrides: -1
O: -2 except peroxides and the OF2 compound.
Compounds w/o H or O: same as ionic charge.
- These take precedence.
CHECK PAGE 477 FOR ANSWERS.
CARRY OUT PPs 9-11, 12a&b ON PAGE 478.
Oxidation: a(n) ___________________ in oxidation number.
Reduction: a(n) ________________ in oxidation number.
PPs #13-15, page 480.
Half reactions of this reaction:
Are the atoms and charges balanced?
Balancing half-reactions in is more complicated when in acidic or basic solutions.
- H+ and OH- need to be taken into account.
Include spectator Ions:
PPs, page 491. #25-28.
SRs, #1-2, 5, 6.
#s 1-7, 9-10, 12