question_answer 84)

  Isotonic solutions must have the same.......... (a) solute                             (b) density (c) elevation in boiling point           (d) depression in freezing point

Answer:

                  (c, d) Isotonic solutions have same osmotic pressure and same concentration. Elevation in boiling point and depression in freezing point are the colligative properties. These two colligative properties depend upon concentration. As the molar concentration is same for isotonic solutions, so elevation in boiling point and depression in freezing point of isotonic solutions must be same.