... ceramics, enamel, paint industryStatus: black or brownish black powder,insoluble in water And ethanol, soluble in acid, liquid ammonium chloride ... ,or according to requirement.Characters : Copper oxide is black to brown amorphous powder or crystalline particles (monoclinic crystals ... 3-4, dielectric constant 18.10, insoluble in water, soluble in acid, ammonia, ammonium chloride, dissolved in sodium ...