An Easy Model for Teaching Mass/Charge in Mass Spectrometry One of the most important challenges to chemistry teachers is helping students to farm visible images of invisible processes or processes that are occurring inside of a machine. Perhaps the best way t o accomplish this task is by using audio-visual resources in the classroom. By taking advantage of these techniques the theoretical exploration will he more motivated.
Thiaartirlewill present a model for thedemonstration of ion deflection by the action of a magnet1 that isorcurring inride of a tube of a mass spectrometer. In this model several small iron balls placed at positron 1 w e figure) are rolled on a inclined lane throuah the mametic field placed at position 2. The balls with different mass will bederlerted dependrng un their mass. The smali halls wilibe deflect& more th& the large halls. This phenomenon is an analogy with the massleharge relations hi^ in the mass soeetrometrv. The bending of iron in a mametic field is due to the ferromaenetic nature of iron, whereas the bending of ions in a mass sperrromerw is due to the furcr acting on s movrng charge by a magnetic field. The simplicity of this m d e l allows the students to comprehend the loair and the application o i mnrs rpectromelry without great difficulty. Acknowledgment. The authors wish t o thank Vitor Francisco Ferreira for his collaboration and the Universidade Federal doRio de Janeiro, the Universidade Federal Fluminense, and the PontiflciaUniversidade Cat6lica for the financial support. ~~
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This work was presented at 4 O Encontro Regional de Quimira-SBQ, maio 1987. ' Silverstein, R. V.: Hassler, G. C.; Murril, T. C. Spertrumetric Idenlificotion of Orgonir Compounds. 4 ed.; Wiley: New York, 1981. Nelson Angelo de Souza Universidade Federal do Rio de Janeiro llha do Fundlo Caixa Postal 1573. C.T.. MA., CEP: 21945 RJ Brasil Univmidade Federal Fluminense Outeiro Slo Jolo Batisla sIn4 Valonguinha Niterbi, RJ. Brasil
Ruleu Van Fossen Bravo PomiAcia Universidade Cat6lica Rio de Janeiro. Brasil
Volume 66
Number 12
December 1989
1039
