question_answer

An aqueous solution of sodium hydroxide is added drop wise to solution of gallium chloride in water. A precipitate is initially formed which dissolves on further addition of NaOH solution. Write chemical equations.

Answer:

                Initially, a gelatinous white precipitate of\[Ga{{(OH)}_{3}}\]  is formed which dissolves in excess of aqueous NaOH solution. \[GaC{{l}_{3}}+3NaOH\xrightarrow{\,}\,\underset{(ppt)}{\mathop{Ga{{(OH)}_{3}}}}\,+3NaCl\] \[Ga{{(OH)}_{3}}+NaOH\xrightarrow{\,}\,\underset{\text{(Soluble}\,\,\text{complex)}}{\mathop{N{{a}^{+}}{{[Ga{{(OH)}_{4}}]}^{-}}}}\,\]