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Give one example of a pseudo first-order reaction.

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Question

Give one example of a pseudo first-order reaction.

Short Answer
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Solution 1

Hydrolysis of methyl acetate:

\[\ce{CH3COOCH_{3(aq)} + H2O_{(l)} -> CH3COOH_{(aq)} + CH3OH_{(aq)}}\]

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Solution 2

Acid-catalysed hydrolysis of ethyl acetate

\[\ce{\underset{Ethyl acetate}{CH3COOC2H5} + H2O ->[H+] \underset{Acetic acid}{CH3COOH} + \underset{Ethyl alcohol}{C2H5OH}}\]

In this reaction, the concentration of water is so large that it practically remains constant.

The rate law of the reactions is

Rate = k0[CH3COOC2H5]

Hence, it is a pseudo-first-order reaction.

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Chapter 6: Chemical Kinetics - Very short answer questions

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SCERT Maharashtra Chemistry [English] Standard 12 Maharashtra State Board
Chapter 6 Chemical Kinetics
Very short answer questions | Q 1
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Chapter 3 Chemical Kinetics
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