Скачать или смотреть How to dissolve euro cents coin with nitric acid. Reaction. Metals. Copper. Chemistry

In this video, we are going to dissolve some euro coins using nitric acid.

The 10 cents coin is made of Nordic Gold. It is a brass alloy, made up from more than 89% of copper, 5% aluminium and 1% zinc. The 1, 2 and 5 Euro cents are made of copper-covered steel.

Copper is oxidized by concentrated nitric acid, to produce Copper ions; the nitric acid is reduced to nitrogen dioxide, a poisonous brown gas with an irritating odor.
When the copper is first oxidized, the solution is very concentrated, and the Copper ions product is initially coordinated to nitrate ions from the nitric acid, giving the solution first a green, and then a greenish-brownish color. When the solution is diluted with water, water molecules displace the nitrate ions in the coordinate sites around the copper ions, causing the solution to change to a blue color.

At the end of the video, we can see the steel of the euro cents. Steel does not react with nitric acid.