A COMPUTER-CONTROLLED CONTINUOUS DILUTION DILATOMETER FOR THE DETERMINATION OF SOLUTE MOLAR VOLUMES AND DIRECT MEASUREMENT OF REACTION VOLUMES IN SOLUTION

The design and operation of a computer controlled continuous dilution dilatometer utilizing a diode array detection system is presented. To test the accuracy and reproducibility of the technique, apparent molar volumes of dilute aqueous solutions of potassium ferricyanide and pot assium ferrocyanide have been measured. To provide supporting data for high pressure studies of reaction volumes and molar volume change in solutions of high ionic strength, study of these electrolytes was exte nded by dilution into 0.1M and 1.0M potassium nitrate solutions rather than extrapolation to zero ionic strength as is normal. In addition, the system has been used to determine reaction volumes of some acid-ba se reactions by direct measurement, using the equipment as an automati c titration dilatometer.