We have found the cuprammonium rayon process to be an excellent system for high school independent study. Meeting twice a week provided time for the student-teacher investigation to result in a productive year of study. One can study the shift of the equilibrium to the complex ion, tetraamminecopper(II) hydroxide, and then return to copper(II) hydroxide by adding saturated copper(II) sulfate. The pH dependence of this equilibrium shift is studied as well as the pH dependence of Schweizer's reagent used to dissolve a-cellulose. The methods for rayon fiber formation and rayon disks are described. The fibers in a cuprammonium rayon membrane for a kidney dialysis machine are pictured.
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Citation
Pickard, Lauren J.; Harris, Mary E. J. Chem. Educ.1999 76 1512.
Keywords
AcidÐBase Chemistry; Demonstrations; Equilibrium; Polymer Chemistry; Introductory / High School Chemistry
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