What is the purpose of the vinegar salt solution in the penny experiment?

The combination of vinegar (a weak solution of acetic acid), and table salt (sodium chloride) helps to dissolve the copper oxide, and also forms the blue copper(II) ion, which is soluble in water. The penny becomes shiny again!

How does vinegar and salt clean pennies?

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 kind of change is salt and vinegar removing tarnish from a penny?

When the salt and vinegar are combined, they form a very small amount of hydrochloric acid. This acid removes oxidation from pennies. Removing the copper oxide is a chemical change. The copper molecules in the vinegar and salt solution settle on paper clips after a period of time, but wipe off easily.

Will vinegar and salt dissolve pennies?

When cleaning a penny, the hydrochloric acid produced by the mixture of salt and vinegar dissolves a thin layer of copper on the penny. Repeatedly allowing copper oxide (the green stuff that looks like dirt on the penny) to form and “cleaning” it will slowly but surely reveal a quick-to-dissolve zinc core.

Why do pennies turn green in vinegar?

Why did the unrinsed pennies turn blue-green? When the vinegar and salt dissolve the copper-oxide layer, they make it easier for the copper atoms to join oxygen from the air and chlorine from the salt to make a blue-green compound called malachite.

What household items can clean pennies?

Start by adding a quarter cup of white vinegar, or lemon juice, into a cup or glass. Mix a teaspoon of salt into the liquid by stirring until it is dissolved. Place your pennies at the bottom of the cup or glass so that they are not stacked on top of each other. Wait about five minutes and check your pennies.

What happens if you add salt to vinegar?

When the vinegar and salt dissolve the copper-oxide layer, they make it easier for the copper atoms to join oxygen from the air and chlorine from the salt to make a blue-green compound called malachite.

Does it devalue coins to clean them?

So what is the best way to clean old coins? It is best not to clean rare coins as removing the patina can significantly reduce the value of them. For this reason, most coin hobbyists almost never clean their coins. In fact, 99% of coins do not increase in value after you clean them, but many will be greatly devalued.

Does Coke really clean coins?

Coke and off-brand colas will quickly remove the tarnish. Just don’t drink the coke afterward. Coke contains phosphoric acid that cleans the oxides. Try a variety of citrus juices to see which works best or simply let your pennies soak in lemon juice.

Why is salt needed when using vinegar to clean Penny?

Cooper Oxide (base) reacts with acids to form water and copper salts. Acetic acid ( C H X 3 C O O H ), which is a weak acid, will react slowly with Copper oxide as compared to H C l which is strong acid. So when use vinegar-salt solution to clean penny, Copper Oxide parellely reacts with HCl and CH3COOH both and gives Copper salt and water.

Is it possible to dissolve a penny in vinegar?

Using the same principles, and a little patience, it is possible to dissolve a penny completely. When cleaning a penny, the hydrochloric acid produced by the mixture of salt and vinegar dissolves a thin layer of copper on the penny.

What’s the best thing to use to clean a penny?

Alternatively, from your research you know that ketchup will clean the penny because it has vinegar and salt in it. You can test ketchup, vinegar alone, saltwater alone, tomato paste alone and vinegar mixed with salt to determine which one works the best. Fill each cup with a few tablespoons of each substance.

What makes a penny look dirty in the air?

The pennies are made of copper atoms, but sometimes the copper atoms combine with other atoms to make molecules. When copper atoms combine with oxygen atoms in the air, they make a molecule called copper oxide, which makes the penny look dirty. Ask yourself what might clean the copper oxide. Create a list of suggestions.