VISCOSITY OF LIQUID WATER FROM 25 DEGREES TO 150 DEGREES C MEASUREMENTS IN PRESSURIZED GLASS CAPILLARY VISCOMETER

An apparatus containing a pressurized glass capillary viscometer has been developed for application in the measurement of the viscosity of liquids over, or near, their atmospheric boiling point. The assembly is pressurized with hydrogen and the diffusion of hydrogen through a palladium-silver membrane is used to lift the test liquid into the efflux bulb of the viscometer. The apparatus provided relative measurement, with an estimated precision of ±0.2%, on liquid water in the temperature range 75° to 150° C. It can be used wherever the presence of hydrogen is compatible with the test liquid. Measured water viscosities, over the range 25° to 150° C, were correlated. The correlation represented the data with an average deviation of ±0.17% and a maximum deviation of 0.49%. Recommended values for water viscosities are given. A detailed description of the apparatus, the experimental method, and results of measurements on liquid water are reported. © 1968, American Chemical Society. All rights reserved.