Cleanning pennies

A penny is a penny, but we can make them shiny and clean with a little help of chemistry. This is another demonstration using vinegar.

NOTE: Don’t use this method to clean collection coins, this can damage the coin. If you have collector coins or valuable items ask a specialist how to clean them.

What we need:

• pennies,
• vinegar,
• salt,
• a jar, with lid
• tablespoon,
• paper napkin.

How to:

1. Mix 2inches of vinegar with 1 tablespoon of salt in the flask;
2. Close the flask;
3. Stir to dissolve the salt;
4. Open the flask and place 2 or 3 coins inside;
5. Close it again;
6. Wait 1 or 2 minutes;
7. Open and remove the coins, be careful with vinegar smell;
8. Place the coins in the paper napkin to dry;

What happens?
The coins become clean and shiny
Why?
The solution we made with the salt and the vinegar released the residues of the coins, and the coins become clean as new.
This residue is copper oxide, this oxide reacts with the vinegar (acetic acid) and the reaction product remains suspended on vinegar.

Et Voilá!
Clean as new
 
Enjoy!