Formation of metallic copper – Coordination complexes

CB-IN-32/EV: This kit enables to observe how a metallic solid appears in a solution containing a salt of this metal. The two original reactants of this reaction exchange their functions: aluminium is dissolved in ionic form, whereas copper settles forming a solid coat. CB-IN-33/EV: This kit enables to observe how coloured coordination complexes come out from two reactions. At the beginning, in both reactions, the metal ions are bound to water molecules (aqua complexes); coming into contact with ammonia or with chloride ions, water molecules are substituted by these ions forming new complexes of different colours. In the case of copper, students can observe the formation of green copper(II) chloride complex, of light blue Cu(II) aqua complex and of the blue copper ammonium complex. In the case of nickel, mixes water-ammonia complexes of various colours can form.