Which statement concerning aqueous sodium hydroxide is correct?
- AWhen it is added to a solution containing sulfate ions, a white precipitate is formed.
- BWhen it is added to a solution of copper(II) ions, a blue precipitate is formed which dissolves in excess to give deep blue solution.
- CWhen it is added to a solution of iron(II) ions, a green precipitate is formed which does not dissolve in excess.
- DWhen it is added to ammonium chloride, a gas is produced which turns blue litmus red.