Title: Silver Tetraiodomercurate(II)
CAS Registry Number: 7784-03-4
Synonyms: Mercuric silver iodide
Molecular Formula: Ag2HgI4
Molecular Weight: 923.94
Percent Composition: Ag 23.35%, Hg 21.71%, I 54.94%
Properties: Deep yellow thermochromic powder. Insol in water or dil acids; sol in solns of alkali iodides or cyanides.
Use: Thermal sensor to detect overheating in journal bearings, etc., becomes blood-red at 40-50° and yellow again on cooling.