1) Hydrogen peroxide, H₂O₂, in aqueous solution at room temperature decomposes slowly and irreversibly to form water, H₂O, and oxygen, O₂, according to the following equation.
2H₂O₂(aq) → 2H₂O(l) + O₂(g) ∆H < 0
a) What effect will increasing the temperature have on the rate of O₂ production? Use collision theory to explain your answer

Solution

b) When a small lump of manganese(IV) dioxide, MnO2, is added to the H₂O₂ solution, the rate of O₂ production increases, but when powdered MnO2 is added instead, the rate of O₂ production is greatly increased. The MnO₂ is recovered at the end of the reaction. State the function of MnO₂ in this reaction.

Solution

c) A solution of H₂O₂ is labelled ‘10 volume’ because 1.00 L of this solution produces 10.0 L of O₂ measured at standard laboratory conditions (SLC) when the H₂O₂ in the solution is fully decomposed. Calculate the concentration of H₂O₂ in the ‘10 volume’solution, in grams per litre, when this solution is first prepared.

Solution