Hot Bath for Samples in Volumetric Flasks It is often required to heat vme,demanding unnecessary work, space, aud e q u i p
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A simple, inexpensive bath was designed in aul. Iaborat,ory which fdfills the ahovementioned requirement.3. A pelfnrrtted, stainless steel "table" top, consiri.ing of a 14 X 8-in. stainless steel sheet war, cut and supported a t each corner by a 4'Iz in.-long screw "leg". Eight,teen S/rin. holes, punched through the sheet, allow ewy iinaertion and withdrawal of 25-ml and 5&ml valumert.rie flasks. The flasks are secured within the holes by retainer rings just, below t,heir growd glaw joint. Cot fmm hard nylon ( 0 , Teflon) 3/3rin.sheeting, the o.d. of the ring equals I-in. and t,hei d . equals in. A llrin. red.ion is cot oat of the ring, permitt,ingit t o be slipped aromd, or removedfmm, the neckof avolnrnert,ricflask. A thermometer is inserted vertically through one of the holes to t,helevel of the hot,t,umof t,he flasks. Either Ihe entire table, or the flasks and thermometer alone, are suspended in the bath remmrnended in a. given procedure. The bath container may be of any appropriate sire and material available. We ,red a 20 X 15 X 2.5 in. Py1.e~ pan filled with water, placed on top of a thermostatically-contded heating unit, to maintain a. nample temperature uf 85" C for several hours. A constant bathlevel can be held against evapm.st,iun by use of a "chicken feeder." The xise of (,he table, the length uf t,he supporting screw legs, the number and diameber of t,he holes, are opt~iunal t o suit individual needs. Greater versatility of the bahle can be obtained by using removable legs, LC., aorews of different, i~~terchangeable lengths to secommodate 100-ml and 250kml volumetric flasks also. If the holes were made to be 1-in. in diameter, retainers having s. 1 s i n . u.d. but differenti.d.'s would serve t,u secure a variet,y of volumetric flask sizes. The table is easily disarsembled and can be shed i n a minimum of drawer npece.
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Journd of Chemical Education
