Excess molar enthalpies of several binary liquid mixtures containing either phenylmethylether (anisole) or benzaldehyde and an aromatic

Abstract

For the 11 binary liquid systems [ xC 6H 5OCH 3+(1− x){C 6H 6, or C 6H 5CH 3, or 1,2-C 6H 4(CH 3) 2, or 1,3-C 6H 4(CH 3) 2, or 1,4-C 6H 4(CH 3) 2, or C 6H 5C 2H 5, or 1,2,4-C 6H 3(CH 3) 3, or 1,3,5-C 6H 3(CH 3) 3, or C 6H 5CH(CH 3) 2}] and [ xC 6H 5CHO+(1− x){C 6H 5C 2H 5, or 1,3,5-C 6H 3(CH 3) 3}], excess molar enthalpies H E have been measured as a function of mole fraction x of either phenylmethylether (PME, anisole, methoxybenzene, C 6H 5OCH 3) or benzaldehyde (BA, C 6H 5CHO) at the temperature T=298.15 K and atmospheric pressure. For these measurements, an LKB differential flow microcalorimeter equipped with two computer-controlled h.p.l.c. piston pumps (from Gilson) was used. For the mixtures of PME with an aromatic, the H E-curves are all positive and rather small, and more or less parabolic; {PME+1,3,5-trimethylbenzene (mesitylene)} exhibits the largest values: H E ( x=0.5)=358 J mol −1. The excess molar enthalpies of the mixtures of benzaldehyde with an aromatic are also all positive and rather small [e.g., for (BA+1,3,5-trimethylbenzene) H E ( x=0.5)=316 J mol −1], though somewhat more skewed than those of the corresponding mixtures with PME.