LAUDA TecInfo Constant Temperature Equipment No. 9 Accurate Temperature Control When Determining Vapour Pressure Curves The vapour pressure of liquids plays a significant role in technology. Technical processes and process components can be improved using vapour pressure data. The more accurately the vapour pressure can be determined, the better it is possible to optimise processes and gain a deeper physical understanding of the procedures. In the faculty of applied chemistry at the Georg-Simon-Ohm University in Nuremberg, a measuring set-up has been developed, which allows dynamic measurement of the vapour pressures of various liquids. For accurate readings, precise temperature control during measuring is decisive.