Without using indicators i thought that...
You could react the solution supposidly containing ammonium ions with NaOH as that would form ammonia, and then react that with gaseous HCl to form a white smoke.
Or does anyone know a simpler method?
Any help appreciated.
just test the ammonia gas given off using damp indicator paper. It is the only (common) alkaline gas..
add a few drops of NaOH first to confirm no precipitate, then add NaOH in excess and either of the tests already suggested.
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