Copper forms two cations, +1 and +2. Cu2+ ion contains in compounds more than Cu+1 ion. In qualitative analysis, there are tests to identify copper +2 ion. Cu +2 ion gives different colours with different reagents. Cu 2+ ion is different from Cu +1 ion.
In this tutorial, you will followings of copper +2 ion
Following tests can be conducted to test Cu2+ ions. At the end of this tutorial, we do several exercises to learn how these experiments are done to test Cu2+ ion in the laboratory to identify from other cations and compounds.
When aqueous NaOH or KOH solution is added to the copper +2 ion solution, a blue - green precipitate of copper(II) hydroxide ( Cu(OH)2 ) forms.
Copper(II) hydroxide is an insoluble hydroxide in water.
When copper(II) hydroxide is heated, copper(II) oxide (CuO) black precipitate is given.
In a basic medium, when hydrogen sulfide gas is treated with aqueous Cu2+ ion solution, A black colour precipitate, copper(II) sulfide (CuS) is given.
A blue green precipitate which does not dissolve in water.
Copper(II) chloride is soluble in water. At solid state, anhydrous copper(II) chloride exist as yellow-brown solid. Also, when copper chloride(II) is at hydrous state, it seems as a blue-green solid.
In the aqueous phase, it is blue green solution. When chloride concentration is high solution become a green and at low chloride concentration, solution is blue.
This is a very famous compound of copper.
In solid state, copper(II) sulfate exist as white (anhydrous) and blue (pentahydrate).
Also CuSO4 is soluble in water like most metal sulfate compounds and forms a blue colour solution.
Copper(II) carbonate is an insoluble carbonate compound in water. In solid state it exists as gray powder.