Question

Why $H_{3}PO_{4}$ is preferred over dil. $H_{2}SO_{4}$ to prepare $H_{2}O_{2}$ from hydrated $BaO_{2}$?

Answer 1

      Phosphoric acid $H_{3}PO_{4}$, is a negative catalyst so it prevents Deuterium $H_{2}O_{2}$ decomposition and also Deuterium $H_{2}O_{2}$ has a strong hydrogen bond than the hydrogen due to its size( that is Deuterium is larger than Hydrogen).

      Because of bonding of hydrogen, water has the high freezing and high vaporization. Hence Phosphoric acid $H_{3}PO_{4}$ is preferred in the preparation of the Deuterium from the hydrated Barium oxide $BaO_{2}$ than the diluted Sulphuric acid $H_{2}SO_{4}$.