We are offering ammonium purpurate ar murexide c.i.no. 56085 (indicator for complexometric titration) (suitable for use in water hardness test) c8h8n6o6 m.w. 284.19 sensitivity for indicator passes test ash max. 0.1% cas no : 3051-09-0 un no. Nr hs code : 2933 59 90 f :