A portable semimicro reaction assembly

a condenser (4) and a line-operated hotplate which allou,s sensitive control of heating (5). A. Gdlenki~mo and Co.. Ltd.. 19 Sun St.. London. E.C. 2. ...
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John T. Stock

Universiw of Connecticut Storrs M. A. Fill

Norwood Technical College London, S. E. 27, England

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Ihe portable reaction assembly shown in Fieure 1 is much more comnact than the nermanentlv asse&bled form previously d&eloped ( I ) , cut it retains most of the versatility of the larger assembly. Since all parts pack into a containing box of approximate closed dimensions 15 in. X 14 in. X Z3/., in., a dozen or more of these sets occupy very little space. An end panel, which is stored beneath assembly panel C, may be attached transversely to the left-hand end of C by means of a single thumbscrew. A rigid, self-supporting assembly is thus obtained. Although mounted in polythene-coated spring clips' which are screwed to the assembly panel as shown, the three-necked generalpurpose flask and the distillation assembly may be a t once removed and replaced by other apparatus. The latter is stored in the lift-out tray D, in the 13/s-in. deep space E below the tray and in compartments F, and G. The lift-out wood block H is suitablv drilled to accommodate such items as crystallizing tubes, filtration assemblies, etc... (1.8) . . . when these are in use. illthough the endpanel is wide a t the bottom to give ample stability, its upper part is narrowed so that the front edge projects some 5 mm only from the face of the assembly panel. This allows overhanging assemblies to be used. Almost reaching the underside of the lid when the box is closed, a wooden pin projects from the face of the assembly panel and thus prevents it from rising during tran~portation.~ Both panels are of a/s-in. thick plywood and are given several coats of hard-surfaced lead-free white or cream paint. The design could be adapted for molding in a suitable plastic. The parts listed in the table are adequate for most purposes and are easily accommodated in the storage spaces provided. Heavy borosilicate glass is used throughout and in most cases each half-joint (standard taper 10/30 or British B.lO) has a single glass hook. A rubber hand stretched between a pair of hooks effectively prevents receivers, flasks, etc., from falling when an assembly is being handled (5). The threenecked flask has a large central opening and is designed for easy cleaning. Convenient miniature accessories are: an electric stirrer equipped with a male cone, which may be inserted directly into the mouth of a flask or the top of a condenser (4) and a line-operated hotplate which allou,s sensitive control of heating (5). A. Gdlenki~moand Co.. Ltd.. 19 Sun St.. London. E.C. 2. England. A commercial version is now available from Aimer Products, Ltd., Rochester Place, London N.W. 1, England.

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Journal of Chemical Educofion

A Portable Semimicro Reaction Assembly

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Portable semimicro reaction a.remb~y indismantled form.

Standard

pa,t

Set of

Apparatus

Part 1 2 3 4 5

7 8 9 10 11 12 13 14

Reflux-and-distil head (2) Reflux-and-addition head Wster condenser Distillation attachment "Nail" filter Filtration receiver R.b. flask Tap funnel Receiver Desiccant tube Threenecked flask Adaptor Gas delivery tube Thermometer adaptor

16 15 17 18 19 20 21 22 23 24 25 26

Stopper Air condenser Microfilter Eared beaker ( 1 ) 50 X 15 mmcrystallizing tube 50 X 25 mm crystallizing tube Teat pipet ( 8 ) Micro pestle Spring clampand ( 1 ) mortar ( 8 ) 6in. thermometer Stirring rod Rubber tubing with adaptors for faucet

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Locations C D C C D D C D C E C E E D

D C E

F

H H G E and H G C D

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" The lettering corresponds with that wed in Figure 1 ( C is

"on pmel").

Literature Cited (1) STOCK,J. T., AND FILL, M. A,, J. CHEM.EDUC.,30, 296 (1953). (2) B i d . , 31,144(1954). J. T., AND FILL,M. A., Chem. Are (London), 71, 933 (3) STOCK, f 1954). (4) STOCK, J. R., AND FILL,M. A,, Lab. Pmetice, 6, 587 (1957). (5) Ibid., 5,344(1956). (6) STOCK, J. T.. A N D FILL.M. A., Metallurgia, 38, 118 (1948).