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Electrochemical Polishing of Silverware: A Demonstration of Voltaic and Galvanic Cells

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Abstract

In this demonstration, the students use their knowledge of electrochemistry to determine that tarnish can be removed from silverware by electrochemically converting it back to silver using items commonly available in the kitchen: aluminum foil and baking soda. In addition to using this system as an example of a galvanic cell, an electrolytic cell is constructed using a battery and a graphite electrode, to first generate a layer of tarnish that can then be removed. Keywords (Audience): High School / Introductory Chemistry

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