Q. The pressure in a liquid droplet of radius r is greater than the pressure of the surrounding equilibrated gas phase by a quantity 2 =r, where is the surface tension.
(a) Consider a droplet of water of radius 1.00 x 10-6 m at 250C suspended in air of the same temperature. The surface tension of water at this temperature is 0.07199 Jm-2. Find the pressure in the droplet if the pressure of the surrounding air is 1.00 bar.
(b) Calculate the difference between the fugacity of H2O in the air of pressure 1.00 bar equilibrated with this water droplet, and the fugacity in air equilibrated at the same temperature and pressure with a pool of liquid water having a flat surface. Liquid water at 250C and 1 bar has a vapor pressure of 0.032 bar and a molar volume of 1.807 x 10-5 m3mol-1.