the microscale laboratory ple in sulfate media. The slope is 0.070V corresponding to n = 0.84. T h e 'H NMR of [Ni(cyclam)ClzlCF3SO~is poorly resolved due to spin-lattice relaxation broadening. A 200 MHz 'H NMR spectrum of [Ni(cyclam)l(CFd303)z in DzO requires 15-20 mg10.5 mL DzO and a n accumulation time of one minute. Following equilibration of the sample, the spectrum reveals resonances a t 19,8.8, -0.5 and -3.2 ppm due to about 15% paramagnetic diaqua species and absorptions a t 1.3, 1.9, 2.4, 2.6, and 3.2 ppm due to the diamagnetic square planar species (10).
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Acknowledgment We acknowledge the participation of students in CHM 343 a t Indiana Universitv-Purdue Universitv Fort Wavne for their cooperation in developing this expehment.
needles can be reduced by using a nylon recoil air hose, 1/4 in. ID and 3%-in. coil. The section of nylon hose is connected to the manifold and the needle with short lengths of PVC tubine are secured with comer .. wire. This solution has pn,ven'to he simpler than inserting thrcc or four turns of a metal Slinkv tov s ~ n n into e the PVC tubine. althoueh this method also works toretract the air hoseU&hen&at outlet is not in use. Literature Cited 1. Mayo, D. W.; me,R M.; Butcher, S. S. Mlelelelele Orgonie Labomfory; New Ymk, Wlley. 1989: p 128. 2. Green, J.A,: Goetl, R. W. J. Chom. Educ. 1631,68,429.
Microscale Preparation of Nickel Formate Dihydrate: A Simple Experiment for the Freshman Lab
Literature Cited
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1. Micheloni. M.: Paoletti. P I n o r ~Chim. Acfo 1980.43. 109 2. Buseh, D.El.~ee. ~ h &Ros, lk8,11,392. 3. Laveeehio, E V.; Gore, E. S.; Buach, D. H. J Am. Chom. Soe. 1974,96,31W. 4 . Chipperfield. J. R.; Woodward. S. J Chem. Educ. 1994, 71, 15 and references therein ~
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Barefield, E. K.; Wagner,F. I w r g S y n l h 1816.16.220 and references therein. Bosnieh, B.;lbbe,M.L.; Webb,G. A.Inorg Chsm. 1965,4,1109. Haines, R. 1.: Mci\uleg A.1nor.c C h . 1980.19. 719. Zeigerson, E.:Ginzburg, G.; SchwarU. N.:Luz 2.; Meyerstein, D. J. Chom. Chsm. Commun. 1879.241. 9. DeAngelis, T P:Heinemann, W R. J. Chem. Educ 1976,53,594. 10. Connollx P. J.;Billo, E. J.I w r g Cham. 1387.26.3224. 5. 6. 7. 8.
An Economical Replacement for Nitrogen in Solvent Removal in Microscale Organic Laboratories Ben Ruekbera University of Flhgde Island Kingston, RI 02881 This paper presents a simple wav to remove solvents from reaction ihixtkes involvingcompokds that are not readily oxidized. For less than the cost of two tanks of nitrogen, a n aquarium air pump' quietly provides a gentle stre& of air, and, with regular oiling,2 is reputed to withstand 10 years of constant use. For mnv&ence;the electric cord was modified by adding a n "in-line switch" (purchased a t a hardware '1 -. store.. The output nipples of the pump were mnnerted to a T-tube which, in turn, was connected with flexible hose to another T-tube. One branch of this latter T-tube was inserted into a very large one-hole stopper stopping a jar, such as a n emotv boiline chin bottle. This arraneement serves both a s a~ pre'ss"ure sd;ty h e 4 and a balla; to reduce the pulsed character of the air flow. The other branch of the T-tube was attached to a length of 20.glass tubing5 filled with plain Drierite with periodic bands of indicator Drierite. A cotton ball placed a t each end of the tube prevents unwanted migration of the Drierite. The other end of the tube was closed by a one-hole stopper fitted with a stopcock leading, by hose, to the manifolds in the hood where the solvent removal takes place.6 With the stopcock closed, the mechanism of the pump slows the difision of water vapor to the drying agent when the apparatus is not in use. ~ i ~ atube r e o f d $ n g agent7 is kept filled and stoppered for easy of the spent . replacement . drying tube. .4lthoLgh quiet, the operating pump is audible and less likely than a nitrogen cylinder to be leR on.' Blunted #13 hypodermic needles provide a robust alternative to Pasteur pipets for directing the air stream. Heat damage to the flexible PVC tubes from the manifold to the A200
Journal of Chemical Education
Francisco J. Arnaiz Laboratorio de Quimica lnorganica Universidad de Burgos 09001 Burgos. Spain Metal formates are relevant in many chemical processes. and nickel formate is also importau
