How will you distinguish between Ammonium hydroxide and Sodium hydroxide using copper sulphate solution?
Answer»
NaOH solution
NH4OH solution
On adding sodium hydroxide to copper sulphate, pale blue ppts. will appear which will not be soluble is excess. CuSO4 (pale blue ppt.)+ 2NaOH ⟶ Cu(OH)2 + Na2SO4
On adding ammonium hydroxide to copper sulphate, pale blue ppts. will appear which will be soluble is excess. CuSO4 + 2NH4OH(pale blue ppt.) ⟶ Cu(OH)2 + (NH4)2SO4 Cu(OH)2 + (NH4)2SO4 + 2NH4OH ⟶[Cu(NH3)4]SO4 + 4H2O (deep blue soluution)