The correct option is- (c) KOH (aq). Phenolphthalein is a synthetic indicator that is used in acid-base titrations. If it is added to an acidic or neutral solution, the solution will turn colourless. The addition of phenolphthalein to a basic solution will turn it pink due to the formation of phenolphthalein ions. As KOH (potassium hydroxide) is a base, the addition of phenolphthalein to its solution will change its colour to pink. On the other hand, all the other solutions are acidic, they ... The colour change observed when the solution of magnesium hydroxide is tested with the following indicators is phenolphthalein turns colourless to pink. What is phenolphthalein ? In an acid-base titration, phenolphthalein is employed as an indicator. It turns pink in alkaline solutions and is colourless in acid solutions as an indicator. Phenolphthalein is colorless in acidic solutions. If you add a few drops of sodium hydroxide (NaOH) solution to the above mixture, the pink color will reappear. This is because the added sodium hydroxide makes the solution alkaline again, and phenolphthalein turns pink in alkaline solutions. What are the limitations of litmus paper and phenolphthalein indicators? Name two other indicators that can be… Get the answers you need, now!
