Studies of Copper I Compounds

Copper (I) compounds are generally obtained by the reduction of copper (II) compounds. CUSO4 will be reduced by SO in presence of Cl ions to form a soluble Na2[CuCl3] complex. 

like other Cu(I) compounds, tends to disproportionate in acid solutions. Cu(II) solutions are formed because of the highly negative enthalpy of hydration of Cu which compensates the extra ionisation energy. 

To an accurately weighed amount of your preparation (0.1 - 0.15 g) add 10 cm of 1.5M sulphuric acid in a boiling tube. Warm, if necessary, until the colour of the solution does not change. Filter through a prepared weighed sintered glass crucible, collecting the filtrate in a clean Buchner flask. Wash the residue with water, dry the 

Cu(l) complexes preferentially coordinate with ligands which are soft bases. The complexes precipitate under appropriate conditions. 

Cul dissolves in concentrated K1 on heating. The [CUI2] anions formed can be precipitated by large cations e.g. [Me4N] or the larger alkali metal ions. The complexes are not stable in water but can be dissolved in some organic solvents. Complexes which contain other halide ligands or a different Cu.i ratio are known but are less stable. 

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