A METHOD for INTRODUCING the LIQUID into the VICTOR MEYER APPARATUS LESTER F. WEEKS Colby College, Waterville, Maine
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NE of the difficulties with the Victor Meyer method for the determination of molecular weights is the trouble experienced when the liquid assigned for the molecular-weight determination is introduced into the vaporizing chamber. Many methods for introducing the liquid have been suggested. R onz io a n d Gagosl and DietzZ have recently proposedcertainmodifications. The method described in this paper is simple in operation and reliable. A container similar to the one shown in Figure 1 or Figure 2 is prepared. The tube shown in Figure 1 is prepared by drawing out apiece of 3-mm. glass tubing to form a capillary and then sealing the larger end. The type shown in Figure 2 is blown from 3-mm. glass tubing and has the advantage of lighter weight for the same capacity . . of liquid. Ronzro AND G~cos,J. Cnmd. Eouc., 9, 1827-8 (Oct., 1932).
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' DIETZ.itid.. 9, 2096-8
(Dec., 1932).
The container is weighed and then filled with the liquid as indicated by Ronzio and Gagos or i t may be placed, capillary end down, in a test-tube containing the liquid. If the test-tube is exhausted when air is re-admitted it will force liquid up the capillary and into the container. The capillary is then sealed and the container weighed. The apparatus for holding the container in the vaporizing chamber consists of a rubber stopper fitted with a piece of 3-mm. glass tubing, which is flush with the lower end of the stopper and extends about 1.5 cm. above it. A piece of rubber tubing about 6 cm. long is fitted tightly over the end of the glass tubing and the open end is closed with a glass plug. The capillary of the container is put through the glass tubing so that it extends about 2 cm. beyond the upper end. A clamp placed over the rubber tubing serves to hold the container in place. (See Figure 3.) When it is desired to introduce the liquid the clamp is bent to one side, breaking the end of the capillary so that the container drops into the vaporizing chamber. The advantages of this method are: the ease with which the containers are prepared, the certainty and convenience of introducing the liquid, and the accuracy with which the weight of the liquid can be determined.
