Absolute Infrared Intensities Of Water-Alcohol Mixtures

The Circle cell method for measuring absolute infrared absorption intensities has been used to study mixtures of water and methanol over the entire concentration range. We have determined values of the real and imaginary refractive indices and dielectric constants in the infrared region between 8000 and 700 cm-1, of the molar conductivity in the same region, and of the integrated areas under the molar conductivity bands. Apart from a discontinuity between 0 and 1% methanol, the latter are linear functions of mole fraction, a result that is expected for ideal solutions but not for mixtures of molecules that interact as strongly as water and methanol.