Does vinegar or coke tarnish a quarter? If it does can you tell me how and why?
Thanks,
Van 7th grade
tarnish
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Christinariehl
- Former Expert
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Re: tarnish
Hi Van,
Vinegar and coke do different things to pennies: coke will remove dark tarnish, while vinegar will create a green tarnish. As you might already know, the dark tarnish on old pennies is created when the copper surface of the penny reacts with oxygen in the air to form copper oxide. Coke contains phosphoric and carbonic acid, which removes the layer of copper oxide to reveal the copper underneath (fruit juice works the same way, with citric acid).
Vinegar, on the other hand, contains acetic acid. The acetic acid reacts with copper to produce copper acetate, which is green in color (that's why the Statue of Liberty is green!!). This is usually referred to as a "patina" rather than as a tarnish.
A chemistry textbook or a teacher might be able to help you figure out the chemical equations for these reactions, or if you get stuck, post another message on this topic!
Christie
Vinegar and coke do different things to pennies: coke will remove dark tarnish, while vinegar will create a green tarnish. As you might already know, the dark tarnish on old pennies is created when the copper surface of the penny reacts with oxygen in the air to form copper oxide. Coke contains phosphoric and carbonic acid, which removes the layer of copper oxide to reveal the copper underneath (fruit juice works the same way, with citric acid).
Vinegar, on the other hand, contains acetic acid. The acetic acid reacts with copper to produce copper acetate, which is green in color (that's why the Statue of Liberty is green!!). This is usually referred to as a "patina" rather than as a tarnish.
A chemistry textbook or a teacher might be able to help you figure out the chemical equations for these reactions, or if you get stuck, post another message on this topic!
Christie
Christie Riehl