Activity coefficients at infinite dilution of 21 organic solutes in the ionic liquid 1-butyl-3-methylimidazolium nitrate ([BMIM][NO(3)]) have been determined using gas liquid chromatography over a temperature range of (303.15 to 363.15) K with the ionic liquid as the stationary phase. The partial molar excess enthalpies at infinite dilution and the solubility parameters of ionic liquid were determined for the solutes from the temperature dependence of the experimental activity coefficient at infinite dilution values.