Question

explain the function of FeCl₃ in the decomposition of H₂O₂ . if we would have used 5.0 ml of 3 m FeCl₃ rather than 4.5 ml of 3 m FeCl₃ , would it have made any difference in the amount of oxygen gas collected? explain why or why not.

Answer 1

FeCl₃ acts as a catalyst in the decomposition of H₂O₂ to expedite the production of O₂ and H₂O. Adding more FeCl₃ beyond the required catalytic amount does not increase the amount of oxygen gas produced if it is not the limiting reactant.

Step-by-step explanation:

The function of FeCl₃ in the decomposition of H₂O₂ is to act as a catalyst, which helps to speed up the reaction without being consumed by it. When FeCl₃ is added to a solution of hydrogen peroxide (H₂O₂), it facilitates the breakdown of H₂O₂ into water (H₂O) and oxygen gas (O₂). This is particularly important in school laboratory settings where a rapid observation of oxygen evolution is desired.

In the context of the amount of FeCl₃ used, using 5.0 ml of 3 m FeCl₃ instead of 4.5 ml would not make a difference in the amount of oxygen gas collected if the FeCl₃ is in excess. This is because once there is enough catalyst to cover all the active sites necessary for the decomposition reaction to proceed at its maximum rate, adding more catalyst will not increase the rate further. Therefore, as long as the stoichiometric ratio of hydrogen peroxide to the catalyst is high enough that the catalyst is not the limiting reactant, the additional FeCl₃ will not increase the amount of oxygen produced.