Calomel

Calomel (CAS 10112-91-1, EC 233-307-5, formula Cl2Hg2) is a mercurous chloride compound, also known by the trade names Calotab, Calogreen, and Cyclosan, and abbreviated in technical literature as Hg2Cl2 or ClHgHgCl. It carries no assigned E-code and is classified within the salts and minerals category.

In electronics, calomel serves as a reference electrode material in electrochemical cells, where its stable redox potential provides a reproducible voltage baseline for precise measurements. In pharmaceutical research and catalysis, it functions as a mercury-based catalyst precursor, facilitating specific reaction pathways where controlled mercury ion release is required under defined conditions.

Calomel is supplied as a crystalline powder grade suitable for laboratory and industrial use, subject to REACH regulation (EC 1907/2006) given its mercury content, which also triggers classification under CLP and relevant RoHS considerations for electronic applications. Procurement teams should confirm current authorization status prior to ordering.