Autocatalytic formation of colloidal mercury in the redox reaction between Hg2+ and Fe2+ and between Hg22+ and Fe2+

✍ Scribed by Raquel R. Raposo; Enrique Meléndez-Hevia; Michael Spiro

• Book ID: 104421001
• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 476 KB
• Volume: 164
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/s1381-1169(00)00203-x

✦ Synopsis

The reaction in perchloric acid solution between Hg 2+ and Fe 2+ was found to proceed extremely slowly until it suddenly exhibited an autocatalytic surge. In conjunction with this rise, a yellow-green by-product formed and disappeared again when the reaction came to an end. In the related reaction between Hg 2+ 2 and Fe 2+ , the autocatalytic behaviour started early and the yellow-green by-product again appeared. No metallic mercury or other solid formed in either reaction, but the production of colloidal mercury was demonstrated by the Tyndall effect and by electrophoresis experiments. A five-step mechanism for these reactions is proposed and incorporated into a computer simulation called Mercury. The behaviour predicted by these simulations agrees well with the unusual experimental findings.