Synthesis, Iodometric Analysis, and IR Spectroscopy of the Peroxide Double Salt [Zn(NH3)4][Mo(O2)4]

• Published in: Journal of chemical education Vol. 97; no. 4; pp. 1120 - 1122
• Main Authors: Young, Charles G, Volaric, Sioe See
• Format: Journal Article
• Language: English
• Published: Easton American Chemical Society and Division of Chemical Education, Inc 14-04-2020; Division of Chemical Education, Inc; American Chemical Society
• Subjects: Ammonia; Chemical synthesis; Chemistry; Coordination compounds; Coordination numbers; Infrared analysis; Infrared spectroscopy; Iodometry; Laboratory Experiments; Peroxides; Science education; Science Instruction; Scientific Concepts; Spectroscopy; Spectrum analysis; Teaching Methods; Thermodynamics; Undergraduate Students; Vibration; Zinc; Hands-On Learning/Manipulatives; Quantitative Analysis; Upper-Division Undergraduate; Coordination Compounds; Synthesis; Laboratory Instruction; IR Spectroscopy; Transition Elements; Titration/Volumetric Analysis
• ISSN: 0021-9584; 1938-1328
• DOI: 10.1021/acs.jchemed.9b01113

This paper describes an upper-division undergraduate exercise involving the synthesis and iodometric and infrared spectroscopic analysis of the peroxide double salt [Zn­(NH3)4]­[Mo­(O2)4]. Here, iodometric methods are employed to determine the peroxide content of the compound, a procedure widely used for the industrial analysis of peroxides. The exercise increases student proficiency in synthesis, the handling of reactive chemicals, and titrimetry, while introducing aspects of metal peroxide chemistry and key chemical concepts related to high-coordination number complexes, kinetic versus thermodynamic stability, and group theoretical treatments of vibration spectroscopy.