Why does vinegar clean a penny?

Answer 1

Clean MoneyI read somewhere that copper pennies can be cleaned by soaking them in olive oil, but some collectors recommend not to clean coins.

Another great way to clean pennies is to use a solution of vinegar and salt. Fill a cup about 1/4 of vinegar and a teaspoon of salt (more salt, faster reaction). The tarnish that forms on a penny is copper oxide. The salt and vinegar create an acid solution that causes the copper oxide to dissolve off the coins. Once they are clean they should have their original shiny coat. Remember though, if there are pits in the pennies they will show now that the oxide has been removed. If you don't have vinegar any acid such as lemon juice or Coke/Pepsi will work as well.

HOWEVER ....Cleaning an ordinary modern penny is fine because there are so many of them. But you should NEVER, EVER try to clean a collectible coin because anything you have at home will damage the coin's surface and reduce or even destroy its value to another collector.
If you clean pennies with just salt, it wouldn't be clean. If you cleaned them with just vinegar, it wouldn't be clean.

Answer 2

Ordinary white vinegar is a dilute form of acetic acid. Because it's acidic, it reacts with the oxidized copper that forms on the coin's surface.

Of course, if you have a coin that's worth a premium as a collectible, you should NEVER try to clean it at home because anything you have - vinegar, soda, Tarn-X, whatever- will damage the coin's surface and reduce its value.

Answer 3

it cleans the pennies because I think it makes things bubbly.

Answer 4

the reason salt and vinger cleans off pennies is because the salt and vinger have a strong formula that cleans off hard surfaces such as a penny