decide if each of the statements about the indicator is true or false. use the images of the flasks to help…

decide if each of the statements about the indicator is true or false. use the images of the flasks to help you choose the correct answers. 1. the phenolphthalein indicator is not affected by the ph of the solution. 2. the phenolphthalein indicator changes colour close to the point of neutralisation which shows the end - point of the titration. 3. when adding acid to base the phenolphthalein indicator changes colour from colourless to pink at the end of the titration.

decide if each of the statements about the indicator is true or false. use the images of the flasks to help you choose the correct answers. 1. the phenolphthalein indicator is not affected by the ph of the solution. 2. the phenolphthalein indicator changes colour close to the point of neutralisation which shows the end - point of the titration. 3. when adding acid to base the phenolphthalein indicator changes colour from colourless to pink at the end of the titration.

Answer

Brief Explanations:

  1. Phenolphthalein is a pH - sensitive indicator. In acidic solutions (pH < 8.2) it is colorless and in basic solutions (pH > 8.2) it is pink, so statement 1 is false.
  2. Phenolphthalein changes color around pH 8.2 - 10 which is close to the neutralization point in many titrations, indicating the end - point, so statement 2 is true.
  3. When adding acid to a base, the solution goes from basic to acidic. Phenolphthalein is pink in basic solutions and colorless in acidic solutions, so it changes from pink to colorless, not colorless to pink, so statement 3 is false.

Answer:

  1. False
  2. True
  3. False