Essential Chemistry for IGCSE - Making And Identifying Salts (Section 3 - No. 34)

What is the purpose of adding aqueous ammonia in testing for the presence of certain ions?

To neutralize the solution

To cause the formation of a precipitate if the ion is present

To act as an indicator

To increase the solubility of the ions

Aqueous ammonia may react to cause a precipitate, and thus identify the presence of certain ions.