Solution thermochemistry of cupric oxide and entropy of the aqueous cupric ion

Abstract

The heats of reaction of CUO-CU(OH)Z-HZO samples with aqueousHClOl have been obtained as a function of concentration. Extrapolated to the normal standard state, the values are AH2098 = -15.00 and -15.3, kcal. per mole for CuO and Cu(OH)*, respectively. These data are consistent with thermochemical paths based on data in the literature. The entropy of Cu'+(aq) has been determined as -21.5 =t 1.5 cal. per mole O K . No evidence was obtained for stable "hydrates" of CuO in the HzO/CuO range 0 to 1.25.