Chlorine is used in water for

Is demineralised or distilled water useful for drinking purposes? If not,how can it be made useful?

The major products during the removal of temporary hardness of water are

The method used to remove temporary hardness of water is

Which of the following hydrides shows the highest boiling point?

Consider the following statements regarding heavy water $(D_2O)$. Which of the following statements is/are correct?
$(A)$ Heavy water is used as a moderator in nuclear reactors.
$(B)$ The power of association is higher in $D_2O$ than in ordinary water $(H_2O)$.
$(C)$ Heavy water is more effective as a solvent than ordinary water.