QQuestion
The metallic hydroxide which forms a deep inky blue solution with excess ammonium hydroxide solution is:
(a) Fe(OH)2
(b) Cu(OH)2
(c) Ca(OH)2
(d) Fe(OH)3
The metallic hydroxide which forms a deep inky blue solution with excess ammonium hydroxide solution is:
(a) Fe(OH)2
(b) Cu(OH)2
(c) Ca(OH)2
(d) Fe(OH)3
(b) Cu(OH)2
Explanation:
Cu(OH)2 reacts with a solution of excess ammonium hydroxide to form a deep blue solution of tetrammine copper [II] sulphate.
Cu(OH)2 + (NH4)2SO4 + 2NH4OH ⟶ [Cu(NH3)4]SO4 + 4H2O
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