An Empirical Formula from Ion Exchange Chromatography and Colorimetry

• Steven D. Johnson ^[1]
  1. [1] Churchill County High School
• Localización: Journal of chemical education, ISSN 0021-9584, Vol. 73, Nº 12 (December), 1996, págs. 1179-1181
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • Experimental determination of the empirical formula for sodium salicylate, Nax(C7H5O3)y, using colorimetry and cation exchange. A Beer's Law plot is prepared for salicylate using 0.0050 M salicylic acid solution. Colorimetric analysis is performed on the salicylate ion in the form of an aqueous ferric complex, which is intensely violet-red, using a simple, inexpensive colorimeter constructed from readily available electronic parts and PVC pipe. Determination of sodium content is conducted using cation exchange, using simple re-usable exchange columns, followed by titration with OH-. The procedure is involved, yet has been conducted by high school chemistry students as a lab final.