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HOW DOES ACID AFFECT DIRTY PENNIES?

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WHAT DOES THE ACID DO WHEN IT CLEANS THE PENNY? BECAUSE I AM DOING A SCIENCE EXPERIMENT IN SCHOOL AND ITS TITLE IS " HOW DOES ACID AFFECT AFFECT DIRTY PENNIES AND CLEAN NAILS?" ME AND MY FRIEND ARE DOING THIS AND REALLY NEED HELP PLEASE RESPOND.

THANKS:) FROM A SCIENCE PROJECT GIRL.

CHIP B
- MILLERPLACE, New York

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How does acid affect dirty pennies?

Billy M.
- Norman, Oklahoma

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Pennies are coated with copper oxide when they are made. The copper oxide makes the pennies look dirty, but they are really not. When the pennies are placed in the acid the copper oxide get dissolved in the acids making the pennies clean.

Linsey R
- Boston, New York

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March , 2009

Hi, Students. Yes, the tarnish is copper oxide, and the acid dissolves the tarnish as Linsey says. But actually the tarnish is not from when the pennies are made (brand new pennies are shiny); the tarnish is from the copper of the penny reacting with the oxygen in the air over time.

There are thousands of students around the world with these same questions, so what we did is we've written a . . .

"Cleaning Pennies FAQ"

. . . which will hopefully answer all your questions on this project. Good luck!

Regards,

Ted Mooney, P.E. finishing.com Brick, New Jersey