Question

State the observation you would make on adding ammonium hydroxide to aqueous solutions of: a)Ferrous sulphate b)Aluminium chloride

Answer 1

1.) A pale green precipitate of Fe(OH)2 is obtained

2.) A white precipitate of Al(OH)3 is obtained

Answer 2

The reaction that will occur when ammonium hydroxide is added to aqueous solution of the given will be

$\mathrm{AlCl} 3(\mathrm{aq})+3 \mathrm{NH} 4 \mathrm{OH}(\mathrm{aq}) \rightarrow \mathrm{Al}(\mathrm{OH}) 3(\mathrm{s}) \downarrow+3 \mathrm{NH} 4 \mathrm{Cl}(\mathrm{aq})$

This reaction is a double displacement and precipitation reaction in a precipitate will occur and the displacement of the atoms will be two times.

Aluminum chloride and the ammonium hydroxide will react by the ions exchange thus forming two new compounds, aluminum hydroxide and ammonium chloride.