A Low-Cost Classroom Demonstration of The Aufbau Principle Students quite often experience difficulty in translating the energy level diagrams presented in undergraduate general chemistry texts into the actual placement of the electrons into their respective orhitals in accordance with Hund's rule. In order to oresent a maohic demonstration of the several faetars involved in the electron distribution in atoms. we have a d o ~ t e d s s\ztenl which not only s h ~ m 111e indwdunl hid-II~ uf the e n q v levels hut also adds srme rehxcu humor t ~ the , diau4m u i q u a m m levels and iub-hell rlrcrnm d~strlhution. 1 'tili,ilng T C ~ ~ I Iiwidihlr Y pll\*tyre~~e rzg c ~ m m uf different
