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Chemical Formula for Reaction - Zinc Plating

2003

I'm going to plate zinc onto copper as you show in the FAQ, "Electroplating--How it Works" as a 6th grade science fair project. If I use a vinegar ⇦in bulk on eBay or Amazon [affil links] , Epsom Salts, and sugar, what is the balanced formula for the chemical reaction? By the way, my dad and I bought a Zinc anode made for a boat for $1.25 at a boat shop. We are going to use it for a Zinc source.

Thanks,

Gina
- Everett, Washington

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2003

That is a great source for zinc, Gina, and I keep forgetting to suggest it; so thanks for reminding us.

The sugar is not part of the "balanced formula for the chemical reaction"; rather it blocks continued plating and crystal growth, inducing the formation of new crystals.

The reaction at the anode is that for each 2 electrons that your battery removes, one atom of zinc goes into solution according to the reaction Zn⁰ - 2e => Zn⁺⁺. These Zn⁺⁺ ions migrate toward the cathode where the 2 electrons are picked up again, causing the reaction Zn⁺⁺ +2e --> Zn⁰.

Epsom salt is MgSO₄,and will ionize to Mg⁺⁺SO₄^--
vinegar (acetic acid ⇦this on eBay or Amazon [affil links] ) is HC₂H₃O₂, and will ionize to H⁺C₂H₃O₂^-, so the solution will contain Zn⁺⁺, Mg⁺⁺, SO₄^--, H⁺, and C₂H₃O₂^- ions. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey