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कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

Why can we not determine the order of a reaction by taking into consideration the balanced chemical equation?

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प्रश्न

Why can we not determine the order of a reaction by taking into consideration the balanced chemical equation?

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उत्तर

Balanced chemical equation often leads to incorrect order or rate law. For example the following reaction seems to be a tenth order reaction.

\[\ce{KClO3 + 6FeSO4 + 3H2SO4 -> KCl + 3H2O + 3Fe2 (SO4)3}\]

This is actually a second order reaction. Actually the reaction is complex and occurs in several steps. The order of such reaction is determined by the slowest step in the reaction mechanism. Order is determined experimentally and is confined to the dependence of observed rate of reaction on the concentration of reactants.

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पाठ 4: Chemical Kinetics - Exercises [पृष्ठ ५६]

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एनसीईआरटी एक्झांप्लर Chemistry Exemplar [English] Class 12
पाठ 4 Chemical Kinetics
Exercises | Q III. 52. | पृष्ठ ५६

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Choose the correct answer from the options given below:


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