Rhodium(III) Chloride, also known as rhodium trichloride, is a red-brown or black crystalline powder that is easily deliquescent. poisonous! Molecular weight 209.26 (anhydrous), melting point 450~500°C (decomposition). Boiling point 800°C (sublimation). To 600°C above to generate polyfluoride. It can be reduced by hydrogen at 70°C. Insoluble in water, acid, aqua regia, soluble in methanol and cyanide solution. In concentrated acid (nitric acid, sulfuric acid) heating decomposition. When heated, it can interact with metals such as sodium, aluminum, magnesium, and iron.