Video: Reaction of copper(II) ion with hydroxide ion
Blue copper(II) ion reacts with hydroxide ion to give a precipitate of gelatinous/flocculent pale blue copper(II) hydroxide. Warming the mixture results in formation of black copper(II) oxide.Cu2+(aq) + 2 OH-(aq) ® Cu(OH)2(s)
Cu(OH)2(s) CuO(s) + H2O(l)