n-Butyl alcohol (BA) is a liquid at standard temperature and pressure, with a boiling point of approximately 117.6? C and a melting point of approximately -89.9? C (Union Carbide Corporation, 1992a). It is less dense than water with a specific gravity of 0.8098 g/cm3 at 20? C (Weast and Astle, 1985). 1. CRC Handbook of Chemistry and Physics, 85th Edition, CRC Press, 2004 2. The RSC Chemspider online chemical databaseiii The Chemspider database contains experimental data and predicted data from ACD/LABS (boiling point only) and EPISuite. The predicted data was only to be used where an experimentally Guide to the CRC Handbook of Chemistry and Physics Physical Constants of Organic Compounds (Section 3) What's in it? boiling point (132.8) and the fact that it is soluble (sl) in water and miscible (msc) only discuss the boiling point minimum type - the one of interest to conservators. Given that restriction, the definition of an azeotrope can become simply: "A liquid mixture of two or more substances that has the lowest boiling point and that boiling point is also lower than any of the pure liquids from which the mixture was combined." In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products: This page contains tables of azeotrope data for various binary and ternary mixtures of solvents. The data include the composition of a mixture by weight (in binary azeotropes, when only one fraction is given, it is the fraction of the second component), the boiling point (b.p.) of a component, the boiling point of a mixture, and the specific gravity of the mixture. DEPENDENCE OF BOILING POINT ON PRESSURE The normal boiling point of a liquid is defined as the temperature at which the vapor pressure reaches standard atmospheric pre ssure, 101.325 kPa. The change in boiling point with pressure may be calculated from the representation of the vapor pressu