Practice with Voltaic Cells

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Practice with Voltaic Cells

• CHEM 32 Supplemental Instruction
• Devin Sprague
• Friday, March 31, 2006

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Identify the following on the voltaic cell
below Which is the cathode compartment? Which
is the anode compartment? Where does oxidation
occur? Where does reduction occur? Which
electrode gains mass? Which electrode loses
mass? Which is the salt bridge?
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Salt Bridge
(loses mass)
(gains mass)
Anion of salt
Cation of salt
e-
e-
M E T A L
M E T A L
I O N S
I O N S
Anode Compartment (-)
Cathode Compartment ()
(reduction)
(oxidation)
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Remember AN OX and a RED CAT
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More practice Design a voltaic cell for the
following reaction Zn(s) Cu2(aq) ? Zn2(aq)
Cu(s) Label the anode and cathode compartments
and show the flow of electrons. Assuming that the
salt bridge contains Na2SO4, show which
compartment each ion would flow to. (Hint you
will need to identify the two half-reactions to
figure out which species is being oxidized and
which is being reduced.)
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Zn(s) Cu2(aq) ? Zn2(aq) Cu(s) Oxidation
Zn(s) ? Zn2(aq) 2 e- Reduction Cu2(aq) 2
e- ? Cu(s)
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More practice Design a voltaic cell for the
following reaction Fe(s) Ni2(aq) ? Fe2(aq)
Ni(s) Label the anode and cathode compartments
and show the flow of electrons.
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More practice Design a voltaic cell for the
following reaction Fe(s) Ni2(aq) ? Fe2(aq)
Ni(s) Label the anode and cathode compartments
and show the flow of electrons.
Cathode (reduction)
Anode (oxidation)
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