Caesium Aquo-chlor-ruthenate, Cs₂Ru(OH₂)Cl₅

Caesium Aquo-chlor-ruthenate, Cs₂Ru(OH₂)Cl₅, is an interesting salt inasmuch as it is isomeric with the first chlor-ruthenite to be discovered, namely, Cs₂RuCl₅.H₂O (vide supra). It is obtained as a buff precipitate on adding alcohol to the blue filtrate from electrically reduced solutions of ruthenium trichloride and caesium chloride. On crystallisation, rose-coloured prisms are obtained. These are soluble in water, and may be recrystallised unchanged from aqueous hydrochloric acid.