Description of experiment
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Needed compounds:
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hydrochloric acid : HCl
hydrogen peroxide : H2O2
copper carbonate (basic) : Cu(OH)2 . CuCO3
Class:
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elem=Cu,O
redox
Summary:
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Copper (II) carbonate gives a very dark compound with H2O2, is this a
peroxide compound or just copper oxide?
Description:
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Add finely divided CuCO3.Cu(OH)2 to H2O2 (15%): The liquid becomes turbid and
cyan, due to the fine cyan powder. After a few seconds, however, the color
slowly becomes darker and the liquid starts bubbling. The evolution of the
gas becomes stronger and the liquid darkens, until it is black and turbid.
Add some HCl (10% by weight) to the black foaming liquid: Sudden violent
foaming (probably a mix of O2 and CO2 is formed), within approximately 15
seconds the liquid becomes completely clear and cyan and stops foaming.
There is a faint smell of elementary chlorine.