Thermochemistry of dichlorobis(NN-dimethylacetamide)-zinc(II), and dichloro(NN-dimethylacetamide)-cadmium(II) and -mercury(II)

Abstract

The standard enthalpy change (ΔH_R^⊖) for the reaction MCl₂(s)+nDMA(I)→[MCl₂(DMA)_n](s)(M = Zn, n= 2; M = Cd or Hg, n= 1; DMA =NN-dimethylacetamide) as measured by solution calorimetry gave values –84.2 ± 1.6 (Zn), –29.2 ± 0.2 (Cd), and 25.2 ± 0.7 (Hg) kJ mol^–1, respectively. The values of the standard enthalpy of formation (ΔH_f^⊖) of the adducts were determined from values of ΔH_R^⊖, and the standard enthalpies of formation of NN-dimethylacetamide and the metal chlorides, giving the values –1 055 ± 5, –698 ± 2, and –527 ± 2 kJ mol^–1 for zinc, cadmium, and mercury, respectively.