The general formula of the unknown compound is Cux(NH3)y(SO4)z a H2O four principal species are present initially in the reaction mixture: copper (II) ions (actually Cu(H2O)62+ ions), ammonia molecules (NH3) , sulfate ions (SO42-), and water. The product of the synthesis is therefore presumed to be formed by the reaction of two or more of these species. Ethanol is also present, but it is an indirect participant in the reaction. In aqueous solutions ethanol, which is miscible with water but of lower dielectric constant (less polar), decreases the solubility of ionic compounds. The marked color change that occurs in the reaction is an important clue to the nature of the product. The product is analyzed for copper (II) ions, sulfate ions, and ammonia molecules. Water is determined as the mass of a sample of the compound that is not accounted for as one of these three species. The analyses to be performed in this experiment are quantitative and are of three types: gravimetric, volumetric, and spectrophotometric. The gravimetric analysis is for sulfate ions; the volumetric analysis is for ammonia molecules; and the spectrophotometric analysis is for copper ions. With careful attention to detail and to technique one can obtain excellent results for each part of the analysis.