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Pennies dissolving in different acids. Why does it happen?

2003

Hey everyone,

I am working on a science project and I need your help. I am going to do an experiment with pennies dissolving in different types of acids but my problem is that I can't find any information about this subject. I am also going to explain why it dissolves. So if you got any information about this subject please reply asap.

Thanks for your help.

Robert W.
- Mosinee, Wisconsin

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Although they are plated with copper, pennies are made of zinc. The copper plating is porous and zinc readily dissolves in most acids.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

I need to know anything you can tell me about what dissolves pennies the fastest. If the liquid is available to an 11 year old, even better. I need the information by 02/25/08, please.(I'll be using this info for my science fair project)I'm in 5th grade.

Savanna M
student - Kissimmee, Fl., United States
February 24, 2008

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Make sure your pennies are from after 1982 so they have a zinc core. Then fold them in half with pliers or a vice and a parent's help, and put two in Coke and two in lemon juice and two in vinegar ⇦in bulk on eBay or Amazon [affil links] and see what happens in a few days. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
February 25, 2008

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Mr.Mooney,
Thanks for that help:)I need more help now! If I want to get the pennies, where do I get them? I need to get some because I don't have very many.

savanna M
student - Kissimmee,FL,US
February 28, 2008

Your neighbor three doors down on the right has a jar of pennies and the woman with the red hair and the small black dog has a change purse full :-)

Seriously, Savanna, that's a question to ask your parents or teacher. I'm sure they can help.

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