Rubidium chloride is an alkali metal halide, chemical formula RbCl, white crystalline powder; lustrous. When heated it decrepitates, melts, and volatizes. soluble in water, slightly soluble in alcohol. In the gaseous state, RbCl is a diatomic molecule with a bond length of about 2.7868A. The bond length increases to 3.285?A in the cubic system, showing a high ionic coordination number in the solid state.
Rubidium chlorides is a source of rubidium metal. Rubidium is usually prepared by the thermal reduction of rubidium chloride.When rubidium chloride and calcium are heated together in stoichiometric proportions at 900-1000°C under a pressure of about 0.02 torr, rubidium distills over.