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The copper in the pennies reacts with the air and forms copper oxide, which is greenish in color. It is a slow process and can be reversed by cleaning the penny with an acidic solution.

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โˆ™ 2010-10-21 17:28:20
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Q: What makes a penny tarnish?
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Related questions

What will happen if you rub ketchup on a tarnish penny and wash it off with water?

i think the tarnish will come of the tarnish penny

How does fruit acid clean a penny?

In the periodic table of Einstein the penny is cleaned by the fruit acid dissolving the copper oxide tarnish the tarnish is then washed away which then shows the true beautiful penny beneath! Or just use sand paper.Also when the acid reacts with the tarnish or whatever you have on the penny the acids reaction is it almost like eats off the tarnish and cleans the penny!

Will a penny rust in rubbing alcohol?

A penny does not rust, it tarnishes. But the penny will tarnish.

Does a penny tarnish?

no, for the 2015 penny

What is penny gunk called?

tarnish :p

Can you remove the tarnish on a penny with spaghetti sauce?


What liquids that take of the tarnish off a penny?


How can you tarnish a penny?

leave it in water 4 a long period of time

How do you tarnish a penny?

With organic matter from fingers (skin oil) sneezing, etc.

Why is the penny i put in curdled milk shiny?

Lactic acid cleans the tarnish from copper

How does acid clean pennies?

By removing some of the copper on the tarnished penny. when tarnish sets on a penny it becomes dull and loses it shine .the acid which acts like a cleanser takes off the build up of tarnish and brings back the shine of the copper that pennies are made of

Why is tarnish an example of chemical change?

Tarnish is an example of chemical change because the oxygen in the air is combining with gold or silver, or whatever the object is made of and makes the tarnish.

Why would a penny become shiny if i put it in curdled milk?

Lactic acid cleans the tarnish from copper

Why does 1977d penny look gold?

i found a gold penny once. try scratching off the gold, like i did. the color scratched off easily and the result is a normal penny. But i dont know how they make gold pennys, or the reason More Information: A penny can tarnish to a golden hue. The environment it is in can cause it to tarnish different colors. For example, gold color, blue color, black color, shades of red color. A penny could be gold plated but it would destroy its numismatic value.

Will cola clean a copper penny?

Soda pop is a mild acid, because of dissolved carbon dioxide. Acid dissolves the copper oxide tarnish that darkens the penny's color.

How much is 1963 golden penny worth?

The US Mint never issued a 1963 golden penny. Sometime the copper cent can tarnish to a golden hue if it is in the right environment.

What is the value of a 1975 Canada penny?

Five cents in completely uncirculated condition. If your penny has any type of wear/tarnish/evidence of circulation, it is just worth face value.

What chemical makes sterling silver tarnish?

Liver of Sulfate

Is salt and vinegar removing tarnish from a penny a physical change?

Physical change

What kind of dirt gets onto pennies?

Bacteria and oils from being handled by people. Tarnish on the copper part of the penny.

Is tarnish a physical or chemical property?

chemical, because when a penny is tarnished its a chemical change because, its weathered down its destroyed. The tarnish itself is usually either the oxide and/or sulfide of the underlying metal.

Does copper rust or tarnish?

It does not rust. It oxidizes and tarnishes. The bright red color of clean, new copper will burnish into a dull brown. Look at a penny... a pre 1982 US penny is 95% copper and 5% zinc.

How cleaning copper tarnish off a penny relates to chemistry?

Tarnish can be removed from a penny by physical means; however, this tends to damage the coin and would not be an acceptable way of handling antique or valuable items. Tarnish itself consists of a number of copper compounds formed from elements and compounds that copper items come into contact with, even those that exposed only to the atmosphere. Some knowledge of chemistry is important to knowing what these compounds are, and how they might be removed, without damage being done to coins in the process.

What makes a better conductor a penny or nickel?


What makes a penny rust?

i know a penny can rust, but im not sure what makes a peny rust! i, too, hope to find out!