WATER VAPOUR PRESSURE MEASURING DEVICE BY COOLING MOIST AIR INCLUDING SATURATED WATER VAPOUR UNDER CONSTANT PRESSURE, WATER VAPOUR PRESSURE DROP MEASURING DEVICE, OR RAOULT'S FIRST LAW CONFIRMING SIMPLE EXPERIMENT DEVICE

摘要

PROBLEM TO BE SOLVED: To easily perform the experiment for Raoult's first law, by measuring the change of volume by utilizing the temperature difference or the change of atmospheric pressure, and determining the water vapour pressure, the saturated water vapour pressure, and the vapour pressure drop by the calculation. ;SOLUTION: The measurement is performed, for example, in such manner that the liquid 3 is inserted into a glass tube of which one end is sealed, by using a glass capillary, the fluid paraffin 2 or the like as a filling agent, is included in the same with the air, and is still put in a large measuring cylinder 4 container for twenty-four hours under a room temperature. The measurement of the change of volume corresponding to the change of temperature is determined by the length of column. The measurement is performed twice by utilizing the change of atmospheric pressure under a condition that the temperature is constant, to determine the measured value of the change of volume, thereby the saturated vapour pressure and the vapour pressure drop can be determined on the basis of the calculation formula. On this occasion, Raoult's first law can be confirmed under a condition that the value of the vapour pressure drop is equal to the mole fraction of the solute. As mentioned in the above, the water vapour pressure can be easily handled in the glass tube or the like, so that the experiment of the Raoult's first law can be performed in the educational field of the later stage secondary education and above.;COPYRIGHT: (C)1998,JPO