For the reaction X_2+ Y + Z → XY + XZ, it is found that the rate equation is rate = k [X_2][Y]. Which of the following might exp

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3 years ago

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For the reaction X_2+ Y + Z → XY + XZ, it is found that the rate equation is rate = k [X_2][Y]. Which of the following might exp

lain why the concentration of Z has no effect on the rate?
A. The concentration of Z is very small and the others are very large.
B. Z must react in a step other than the rate determining step.
C. Z is an intermediate.
D. The fraction of molecules of Z that have very high energies is zero.
E. The activation energy for Z to react is very low.

Chemistry

1 answer:

iogann1982 [59] · Answer 1 · 2022-07-24T13:08:19+03:00

Answer: C. Z is an intermediate.

Explanation: The given reaction is $X_{2} + Y + Z \rightarrow XY + XZ$

And the rate equation is rate = k [X_2][Y]

From this, we can imply that either the concentration of Z is very small in comparison tot he other reactants or the reactant Z is an intermediate which is available only for the given small amount of time.

There can be various steps in the mechanism for the proposed reaction and Z can also react in any of the steps. It is not necessary that it should react in a step other than the rate determining step.

This might be possible that the activation energy for Z to react is very low But since it has made a new kind of product that is XZ, then the former cannot be true.