Q4. lodide ions are oxidised to iodine by hydrogen peroxide in acidic conditions. H₂O₂(aq) + 2H+(aq) + 21-(aq) → 1₂(aq) + 2H₂O(l) The rate equation for this reaction can be written as rate = k [H₂O₂] [-]³ [H*]c In an experiment to determine the order with respect to H*(aq), a reaction mixture is made containing H*(aq) with a concentration of 0.500 mol dm-3 A large excess of both H₂O₂ and 1- is used in this reaction mixture so that the rate equation can be simplified to rate = k₁ [H*]c (a) Explain why the use of a large excess of H₂O2 and I means that the rate of reaction at a fixed temperature depends only on the concentration of H*(aq). (b) Samples of the reaction mixture are removed at timed intervals and titrated with alkali to determine the concentration of H*(aq). State and explain what must be done to each sample before it is titrated with alkali.

Q4. lodide ions are oxidised to iodine by hydrogen peroxide in acidic conditions. H₂O₂(aq) + 2H+(aq) + 21-(aq) → 1₂(aq) + 2H₂O(l) The rate equation for this reaction can be written as rate = k [H₂O₂] [-]³ [H]c In an experiment to determine the order with respect to H(aq), a reaction mixture is made containing H(aq) with a concentration of 0.500 mol dm-3 A large excess of both H₂O₂ and 1- is used in this reaction mixture so that the rate equation can be simplified to rate = k₁ [H]c (a) Explain why the use of a large excess of H₂O2 and I means that the rate of reaction at a fixed temperature depends only on the concentration of H(aq). (b) Samples of the reaction mixture are removed at timed intervals and titrated with alkali to determine the concentration of H(aq). State and explain what must be done to each sample before it is titrated with alkali.

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter11: Chemical Kinetics

Section: Chapter Questions

Problem 11.96PAE: The following statements relate to the reaction for the formation of HI: H2(g) + I2(g) -* 2 HI(g)...

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