JOURNAL OF CHEMICAL EDUCATION
A CONTINUOUSLY WEIGHABLE REFLUX APPARATUS CHARLES E. WHEELOCK Lafayette, Indiana
THE
apparatus illustrated in Figure 1 has been found useful in reactions requiring the introduction of a gas into a liquid medium and determination of the degree of reaction by gain in weight of the reaction mixture. As shown in Figure 1, the apparatus consists of a tall-form beaker heated by a Glascol mantle and a water-cooled condenser through which passes a hollow stirrer for simultaneous agitation and introduction of gas. The condenser and stirrer bearing is made from a 200-ml. round-bottom flask whose bulb has been expanded just to fit inside the beaker. An open piece of 10-mrn. (I.D.) tubing sealed a t A and B serves as a stirrer bearing. Cooling is accomplished by water flowing into the supported tubeat C and out a t D. In operation, the beaker and heater are placed on a balance pan, the combination condenser and stirrer bearing is clamped as shown in Figure 1 so that the beaker may move vertically without binding and on the other balance pan are placed tare weights to balance the beaker, heater, and reaction charge, and also weights correspondimg to the amount of gas to be absorbed. Stirring and refluxing are started and gas is introduced into the chamber at E. Lubricated rubber seals a t F and G prevent escape of the gas, which enters the hole H, passes down the hollow stirrer and leaves a t the fine openings I. In order to prevent solvent loss, gas should be introduced a t a rate not much greater than the rate of absorption.
