Oxidation and Reduction
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Edwina Nelson William W. Carter
5740 South Michigan Ave.
Chicago, Il 60637
Grade Level 8th
To construct an electroplating device.
To describe chemical changes that involve the transfer of electrons.
To describe the procedures used and the reactions occurring during the
electroplating of a metal.
300mL beaker 6 volt battery
Alligator Clips Copper sulfate solution (CuSO4)
Copper Strip Spoon
Draw large cartoon on board. Student bringing a RED-OX to class-explaining
very defensively that; "The book said the class would be studying RED-OX
behavior." Say, "Class-How's this REED OX-He eats REEDS in the forest and takes
naps in the afternoon." What do we mean by- ReDox? Today we will participate in
an activity, "YOU CAN'T LOSE FOR WINNING", (printed on board). Explain to
students that Electroplating (today's activity) is a form of oxidation-reduction.
Say to students, "We will now collect materials placed on the Lab table, take one
of each. Working in groups, students set up electroplating apparatus. Directions
are given on lab sheets; Pour 150mL of the Copper Sulfate solution in a 300 mL
beaker. Place the spoon and the copper strip in the solution. CAUTION: THE SPOON
AND THE COPPER STRIP SHOULD NOT TOUCH. Attach one alligator clip to the spoon
(the metal being reduced). Attach one alligator clip to the copper strip (the
metal being oxidized.) IMPORTANT: Connect the spoon to the negative terminal of
the battery and the copper strip to the positive terminal. Wait approximately 5-7
minutes for a reaction. The students should observe the color of the solution.
Red copper color is evident on the spoon. Disconnect the alligator clips, remove
the spoon and copper strip from solution, observe end of copper strip that was
attached to alligator clip and discuss observations. Discuss the value of
electroplating. Concepts students should comprehend are that oxidation is a loss
of electrons, reduction a gain of electrons. The battery supplied the extra
electrons. The (Cu) ions in the solution combine with the extra electrons on the
object to be plated. The copper strip becomes oxidized (loses electrons) and the
spoon becomes reduced (gains electrons).