Temperature Dependence of Adiabatic Compressibility

IT is well known that the adiabatic compressibility βφ of a liquid increases fairly rapidly with rise in temperature. The rise becomes more rapid as the temperature increases. With many liquids the adiabatic compressibility increases by about 60 per cent for a rise of temperature from 0° to 60°, or 1/√βφ decreases by 21 per cent. A large part of the high initial compressibility of ordinary liquids is connected with the nearness of the critical point liquid gas, for compressibility in the gas phase is high and at the critical point itself compressibility is infinite1. Hence the absolute value of the compressibility depends on how far the temperature is from the critical point.