Science experiment: Coin cleaner

So what would clean a coin? Check out these science experiments and other great science tips and tricks for kids. Science is great fun for everyone.

What you need:

• a few old coins (which aren't shiny)
• vinegar
• salt
• bowl
• paper towels

Number of players:
1+

Activity:

Add 1 teaspoon of salt to 1/4 cup of vinegar.

Stir thoroughly.

Place old dirty coins into the bowl.

Wait for 20 seconds and then take the coins out and rinse them in water and dry them with your paper towels.

They should be now be shiny and clean!

Why? Vinegar is an acid and the salt reacts with the acid in the vinegar which removes the copper oxide that was making your coins look dirty.