An aqueous solution turns red litmus solution blue. Excess addition of which of the following solution would reverse the change? (a) Baking powder (b) Lime (c) Ammonium hydroxide solution Hydrochloric acid

• Soln:

Answer is (d) Hydrochloric acid Explanation:

If the solution turns red litmus to blue color then the solution should be basic in nature. Its effect can be neutralized by adding an acid hence (d) Hydrochloric acid is the answer.