MAY, 1948
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DISPLACEMENT OF HALOGEN E. C. GILLETTE, JR., and F. 3. ROSE United States Military Academy, West Point, New York
base end. The opened ends are ground to maintain a gas tight seal with the glass cover plate. One cylinder is twice the volume of the other. The diameters are identical so that the two cylinders can be mounted vertically and axially with the opened ends together over the hole in the box with the light beams passing through the box. The gases must be carefully prepared and stored in Clr + 2HI 2HCl L the cylinders by placing a well-greased cover plate 1 "01. 2 vols. over the mouth of each cylinder. Chlorine gas is A box large enough to house a bright light source, placed in the smaller cylinder, and hydrogen iodine in e. g., a 35-mm., 115-volt projector, arranged to project the larger one. A fairly weak concentration of each vertically through a hole in the top is used to support gas works best. For demonstration, place the box in a suitable two glass cylinders. The glass cylinders have wide bases and heavy ring necks, and are each closed at the location and place the HI cylinder (heavier gas) base
T E E RELATIYE chemical activity of two of the halogen group of chemical elements can be strikingly demonstrated by displacing iodine in combination by chlorine, both reagents being initially in the gaseous state. These reagents may be easily prepared and maintained in the gaseous state under normal conditions. The applicable equation is:
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down in an upright position and center over the light escape of any gas. The help of an assistant will be source hole. The chlorine cylinder is then inverted required at this point. The gases will interact vigorously as the lighter gas and placed on top of the HI cylinder. Both cover plates are left in position. Thus, with the cylinders diffuses downward into the heavier one. Purple iodine mouth to mouth, the light is switched on and the two vapor will be noticeable and sparkling iodine crystab cover plates are slipped out with care to minimize the will rain down into the iower cylinder.
