Concept:Ammonium chloride is a salt formed from a strong acid (HCl) and a weak base (NH₄OH). Its aqueous solution is acidic. Acids turn blue litmus red.Explanation:First, identify the nature of ammonium chloride. It is a salt of hydrochloric acid (strong acid) and ammonium hydroxide (weak base). When dissolved in water, it undergoes hydrolysis, producing H⁺ ions. This makes the solution acidic. Litmus is an indicator: blue litmus turns red in acidic conditions, while red litmus stays red. Therefore, a solution of ammonium chloride will turn blue litmus red.
