Why does vinegar clean pennies?

In this brief guide, we will answer the question, “why does vinegar clean pennies,” and discuss what happens when you soak a penny in vinegar and what is the science behind cleaning pennies with vinegar.

Why does vinegar clean pennies?

Vinegar cleans pennies because of its acidity, which makes it an effective cleaning agent.

Vinegar is a liquid made from the fermentation of ethanol, and its acetic acid content can range from 5% to 20%. Vinegar’s acidity is responsible for its sour taste and ability to clean metal. 

When vinegar is used on a penny, the acid in the vinegar reacts with the metal in the penny. The reaction causes the tarnish on the surface of the penny to be removed, thus resulting in a shiny, clean-looking penny.

What happens when you soak a penny in vinegar?

A chemical reaction occurs when you soak a penny in vinegar. The first thing to know about pennies is that they’re made of two different metals: copper and zinc.

When you put your dirty pennies in the vinegar, the copper oxide and some of the copper dissolve in the water. That means some copper atoms leave the penny and start floating around in the liquid, making it look clean.

So now there’s a bunch of copper atoms floating around in this solution, what happens next? Well, for one thing, it turns out that those copper atoms are positively charged. And guess what else is positively charged?

All those zinc ions that are still stuck to your penny (all ions are electrically charged.) So now these positively charged zinc ions start flipping over to the other side of the penny to connect with all those positive copper atoms floating around in the solution.

But once they flip over, they’re still just plain old regular zinc atoms. And because they’re not covered by another layer of metal (unlike when they’re on the other side of your penny), those zinc atoms turn back into zinc ions, and then get picked up by your vinegar and salt solution and float away!

Why do pennies clean in vinegar and salt solution?

Pennies are cleaned in vinegar and salt solution because vinegar and salt react to dissolve the copper oxide, which forms when copper from coin gets reacted with oxygen in the air.

Because pennies are made of copper, they can turn dull overtime when the copper reacts with oxygen in the air and water. This reaction is called oxidation, which is when a chemical reaction causes an element to lose electrons. In this case, copper oxide forms on the penny.

When you put a penny in vinegar and salt, the vinegar and salt react with each other to dissolve the copper oxide. The salt helps to break up the copper oxide even faster than just using vinegar.

What is the science behind cleaning pennies with vinegar?

When you put your dirty pennies in the vinegar and salt, the copper oxide and some of the copper dissolve in the water. That means some copper atoms leave the penny and start floating around in the liquid. But when these copper atoms leave the penny, they leave some of their electrons behind.

The salt is just there to make sure that all of the copper ions, the positive charges that are left behind when we pull out electrons, can float around freely in a solution. The salt also helps to neutralize any negative charges on our vinegar molecules so that they don’t get in the way of our positively charged copper ions either.

Now, what we have here is a positively charged pool of copper ions floating around in the solution. These positive charges attract free electrons back to our pennies. It’s a nice little cycle where some copper atoms dissolve and then others reattach themselves to the pennies.

In this way, we can clean off all of those yucky green copper oxide layers from our pennies so that they’re nice and shiny again!

How to clean bulk pennies in vinegar?

The best way to clean pennies in bulk is to use vinegar.

It’s easy and effective! Here’s how:

1. Find a bowl or container that you can submerge your pennies in.

2. Put your pennies inside the container or bowl, then pour in vinegar until they are covered by at least 1/2 inch of liquid.

3. Let the pennies sit for about 5 minutes before removing them.

4. Remove the pennies from the vinegar, rinse with water, and check out their new shine!

How does copper in pennies react with acetic acid in vinegar?

Copper and other metal ions react with acetic acid, which is a weak acid. The acetic acid donates protons to the copper atoms, which are then released into the solution as ions. The reaction is shown below:

Cu(s) + 2CH3COOH(aq) –> Cu2+(aq) + 2CH3COO-(aq) + H2(g)

Other FAQs about Vinegar that you may be interested in.

What can i use instead of red wine vinegar

What can I substitute for white vinegar?

Does balsamic vinegar have alcohol?

Can you eat vinegar with acid reflux?

Conclusion

In this brief guide, we have addressed the question, “why does vinegar and salt clean pennies,” and other questions related to the subject, such as what happens when you soak a penny in vinegar and what is the science behind cleaning pennies with vinegar.

Citations

https://frugalfun4boys.com/simple-chemistry-experiment-clean-pennies-with-vinegar/

https://www.exploratorium.edu/science_explorer/copper_caper.html#:~:text=When%20you%20put%20your%20dirty,floating%20around%20in%20the%20liquid.

http://www.planet-science.com/categories/under-11s/chemistry-chaos/2011/03/chemistry-cleans-pennies.aspx#:~:text=How%20does%20it%20work%3F,and%20remove%20the%20copper%20oxide.

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