EXCESS VOLUME OF MIXING FOR BINARY-MIXTURES OF SOME NITROALKANES AND SYMMETRICAL AROMATIC-HYDROCARBONS

The excess volume of mixing (V(E)) for the binary mixtures of the nitr oalkanes nitromethane, nitroethane, and 2-nitropropane with symmetrica l aromatic hydrocarbons benzene, p-xylene, and mesitylene has been det ermined by density measurements at 293.15 K. The V(E) values are posit ive over the whole mole fraction range except those for the mixtures o f nitroethane and 2-nitropropane with benzene and p-xylene where they are negative at lower and positive at higher mole fractions of nitroal kanes. The results have been discussed in terms of dipole-induced dipo le electrostatic molecular interactions significantly affected by ster ic factors.