EXCESS PARTIAL MOLAR VOLUMES AND THERMAL EXPANSIVITIES IN THE WATER-RICH REGION OF AQUEOUS 2-BUTANONE

Excess partial molar volumes of 2-butanone V(m)E(B) and thermal expans ivities alpha(p) were measured in the water-rich region of aqueous 2-b utanone. The composition derivatives of both quantities showed anomali es at about X(B) = 0.033 (x(B) is the mole fraction of B). (partial de rivative V(m)E(B)/partial derivative n(B))p,T,nW showed a step anomaly , while (partial derivative alpha(p)/partial derivatives n(B))p,T,nw e xhibited a peak anomaly. The compositions at which these anomalies occ urred match those of the step anomalies observed earlier in (partial d erivative H(m)E(B)/partial derivative n(B))p,T,nW and (partial derivat ive S(m)E(B)/partial derivative n(B))p,T,nW in aqueous 2-butanone. The se results are discussed in comparison with those obtained previously for aqueous 2-butoxyethanol.