question_answer 99)

  Phosphoric acid is preferred over sulphuric acid in preparing hydrogen peroxide. Why?

Answer:

  In the preparation of \[{{H}_{2}}{{O}_{2}}\] from barium peroxide and sulphuric acid, the use of sulphuric acid has a disadvantage as it catalyses the decomposition of \[{{H}_{2}}{{O}_{2}}\] formed. In place of\[{{H}_{2}}{{O}_{2}}\], weak acids like ortho phosphoric acid, carbonic acid are preferred. All heavy metal impurities present in\[Ba{{O}_{2}}\] are removed as insoluble phosphates and decomposition of \[{{H}_{2}}{{O}_{2}}\]is prevented.