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Karnataka Board PUCPUC Science 2nd PUC Class 12

Which of the following graphs is correct for a first order reaction?

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Question

Which of the following graphs is correct for a first order reaction?

Short/Brief Note
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Solution

Explanation:

The pace of a reaction that is directly proportional to the concentration of the reacting substance is known as a first-order reaction. 

A first-order reaction's kinetic equation 

k = `2.303/t log  [R]^0/([R])`

The Y-axis represents concentration, whereas the X-axis represents time.

`log = [R]^0/([R]) = (kt)/2.303`

`[log = [R]_0/([R])] = [(kt)/2.303](t)`

y = mn

k = `2.303/t log  a/(a - x)`

t = `2.303/k log  a/(a - x)`

x = `a - a/2`

x = `a/2`

`t_(1/2) = 2.303/k log  a/(a - a/2)`

`2.303/k log 2`

`t_(1/2) = 0.693/k`

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Chapter 4: Chemical Kinetics - Exercises [Page 55]

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NCERT Exemplar Chemistry Exemplar [English] Class 12
Chapter 4 Chemical Kinetics
Exercises | Q II. 32. | Page 55

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