General Description
Dark brown crystals.
Reactivity Profile
PALLADIUM CHLORIDE(7647-10-1) is a weak oxidizing agent. PALLADIUM CHLORIDE(7647-10-1) is reduced in solution by hydrogen or carbon monoxide to metallic palladium. . Decomposed at high temperatures to metallic palladium and chlorine.
Air & Water Reactions
Deliquescent. Water soluble.
Fire Hazard
Flash point data for this chemical are not available. PALLADIUM CHLORIDE is probably combustible.
Chemical Properties
Palladium chloride is a dark brown powder, hygroscopic (absorbs moisture from the air). It is incompatible with acids, aluminium, ammonia, magnesium, nitrates, zinc, heat, thiocyanates, and organic solvents. Thermal decomposition of palladium chloride may release chlorine, hydrogen chloride, and oxides of palladium. It is used as a catalyst, photographic, and electroplating reagent. Palladium and its alloys are used as catalysts in the (petro)chemical and, above all, in the automotive industries. Applications of palladium compounds for electronics and electrical technology include use in metallisation processes (thick film paste), electrical contacts and switching systems, in the synthesis of semiconducting metal-containing polymers in which the polypyrrole backbone has a conformational energy minimum and is nearly planar. Palladium chloride is a stable chemical substance and is incompatible with strong oxidising agents.
Physical properties
l Properties Red rhombohedral crystal; hygroscopic; density 4.0g/cm3; melts at 679°C; dissolves slowly in water; also soluble in ethanol and acetone; dissolves rapidly in hydrochloric acid.
Definition
ChEBI: Palladium(II) chloride is a palladium coordination entity consisting of palladium(II) bound to two chlorine atoms. It has a role as a catalyst.
Preparation
Palladium dichloride is prepared by dissolving palladium metal in aqua regia or hydrochloric acid in the presence of chlorine. Alternatively, it may be prepared by heating palladium sponge with chlorine gas at 500°C.
Purification Methods
The anhydrous salt is insoluble in H2O and dissolves in HCl with difficulty. The dihydrate forms red hygroscopic crystals that are readily reduced to Pd. Dissolve it in conc HCl through which dry Cl2 is bubbled. Filter this solution which contains H2PdCl4 and H2PdCl6 and on evaporation it yields a residue of pure PdCl2. [Grube in Handbook of Preparative Inorganic Chemistry (Ed Brauer) Academic Press Vol II p 1582 1965, Mozingo Org Synth Coll Vol III 685 1955.]
