Question

Below is a reaction scheme that many students who are/were new to air-free techniques (i.e., Schlenk techniques) may be familiar with: MC Zn dark-green dark-red MeCN NCCHE NCCHE NCCHE NCCHE yellow blue a. What kind of light (color) is absorbed to show the listed colors for each of the four complexes above? b. What are the oxidation states of Titanium in the blue and in yellow complexes? Confirm your answers by reading this paper: Burgmayer, S.J.N. "Use of a Titanium Metallocene as a Colorimetric Indicator for Learning Inert Atmosphere Techniques" Journal of Chemistry Education, 1998, 75. Based on what you know about the relationship between oxidation states of a metal and the relative splitting, rationalize why the bottom left (yellow) complex is not green.

Answer 1

Red Color of Complex light cohid absorbey. Dark red Green Durk green yellow Voilet blue Orange & Color observe any alwage the Complementy colors of the light which is absorbed. ② . Oxidation stute of Titanium yelloco Complex Cyclopentadienyl (0 = -1 charge) NCCH3 is sondey in newtry form (pec) chayr =0 so in yellow complex 2 X (-1) + 2X (0) +2=+2 (T, +4) Blue Complex similert IX (4) + 2x0 t n = fl x = +4 a = t ]