Syringes as Pipet Fillers Continued emphasis has been placed on laboratory safety during the past 10years and this emphasis should be continued. One area in which laboratory safety concerns instructors when students are learning basic skills in chemistry is pipeting. Students in general chemistry a t the collerce and high school level must he reminded constantlv not t o nioet bv mouth. ~ecentl;articles1 explain-the use of pipet bulbs which are inexpensive and safe touse. ~nfort&tely,.to the inexperienced student, the rubber bulb method is somewhat cumbersome. If a solution is withdrawn into the rubber bulb by accident, the student is reluctant to admit hisher guilt, and the next user is likely to contaminate the pipet and sample. Even if it is known that the bulh has a liquid within it, there is a problem in cleaning and drying it. I t is proposed here that a syringe he used to draw solutions into a pipet. The syringe Luer tip is fitted with a piece of Latex tuhing about 2 cm in length t o which the pipet can he attached. A wire Loop attached to the piston allows the operator to contnrl the vchrne of liquid in the pipet airh h i s h r r furefinger. This airemhly is found to be adequate for hurh rmnqfrr pipets as well an for Mohr ryper. The syringe has a posiriw nfferr ou the meniscus of the liquid contained in h n h the fi.iinr and emmvine .. - mode,. In comparison to many other commercial pipet fillers, syringes are rather inexpensive. The list prices of syringes in the required volume range are: 10-mL $0.20 and 30-mL $0.72 each. Volume purchasing can reduce these costs. The list price of a rubber bulh is just under $2.00. At these prices each student laboratory drawer can be equipped with a syringe. If the harrel becomes contaminated, it is simple to dismantle the syringe, clean, dry, and reassemble it.
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Knevel, A. M., J. CHEM. EDUC., 57,285 (19801, Deckey, G. J., J. CHEM. EDUC., 57,526 (19801,D~W m , H. D., J. CHEM. EDUC., 58,733 (1981). Richard A. Hermens Eastern Oregon State College La Grande. OR 97850
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