Chemistry cleans pennies!

Chemistry cleans pennies!

Clean your pocket money

Chemistry cleans pennies...

We need chemistry for lots of things - medicine, computers and cars. How about using chemistry to clean your pocket money? What do you think of when you hear "salt and vinegar"? Crisps? Chips? You can use salt and vinegar to clean your pennies!

What you need:

  • Dirty pennies
  • White vinegar
  • Table salt
  • Shallow glass or plastic bowl

How to:

  1. Put a couple of your dull, dirty pennies in the bowl.
  2. Cover the pennies with salt.
  3. Pour white vinegar over the pennies.
  4. Rub the salt and vinegar mix over both sides of the pennies.
  5. Take the pennies out and wash off the salt and vinegar mix.

What do you see? The pennies should be much shinier.

This video shows you what to do:

How does it work?

Pennies get dull and dirty because the copper in the pennies reacts with oxygen in the air to form copper oxide. When you put your pennies in a vinegar and salt mix, the vinegar and salt react together and remove the copper oxide.

What happens if you don't wash the pennies once you've taken them out of the salt and vinegar mix?

Try it and see!

Have you tried it yet? Leave the pennies on a paper towel and wait for about an hour. The answer is below the picture.

One cent_med411039

If you don't wash the salt and vinegar mix off, a blue-green layer forms on the pennies. The salt and vinegar mix speeds up the reaction between copper and oxygen in the air, forming copper oxide - which is a blue-green colour. It's the same reaction that makes the Statue of Liberty green!

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