Boiling Point of Capillary-condensed Water

Abstract

A CONSIDERABLE amount of experimental work on freezing-point depressions of capillary condensates has been reported in the literature in recent years¹. Carman² has given an account of a few more properties in which capillary-held liquids differ from the same materials in bulk conditions. Boiling points of condensates, however, do not appear to have been studied in detail. We have devised a simple method for this purpose. The apparatus, in its essentials, consists of a small vessel, which contains the capillary system under examination; it is connected to a vacuum pump as well as to a suitable differential manometer and is placed in an oil-bath, the temperature of which can be gradually raised. The vessel is first evacuated, and the manometer then registers the vapour pressure of the liquid under examination. The temperature of the bath is then gradually raised until the vapour pressure becomes equal to the atmospheric pressure. The temperature recorded then is the required boiling point.