Question

Find and discuss example of a reaction with zero order kinetics. Compare the kinetics of this reaction with a different reaction, which has either first or second order kinetics. Your response should be at least two paragraphs. Provide citations and references.

Answer 1

Hello!!!

Zero order kinetics is the reaction kinetics where the progress of reaction is dependent on the zeroth power of reactant concentration or in simple words , is independent of reactant concentrations.

Some of the examples of zero order kinetics are: -

1) Reverse haber process

In the reaction,

         2NH₃ ------> N₂ + 3H₂

The rate of reaction is independent of the concentration of ammonia.

2) Decomposition of N₂O in presence of Pt wire

N₂O decomposes in the presence of platinum wire to give N₂ and O₂ and the reaction is independent of the concentration of N₂O.

In the reactions having either first order or second order kinetics or basically the reactions in which the rate of reaction is dependent on the substrate concentration, the rate is directly proportional to the n^th power of the reactant concentration where, n= order of reaction.

In all such reactions we can modify the rate of reaction by just increasing or decreasing the substrate concentration whereas in zeroth order reaction, change in substrate concentration will not influence the rate of reaction. Moreover, first order or second order reactions can be limited to zeroth order kinetics by taking the substrate in large excess such that slight change in concentration of reactant have no influence on overall concentration. In all the first, second or nth order reactions, the rate of reactionis thus dependent on both in initial and final concentrations whereas in zeroth order it is only dependent on the initial concentration of reactant.

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