CameraIcon

SearchIcon

MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Arrhenius Equation

A reaction ta...

Question

A reaction takes place in three steps with an individual rate constant and activation energy, as given below.
Rate constant Activation energy
Step 1 $k_{1}$ $E_{a_{1}} = 180 k J / m o l$
Step 2 $k_{2}$ $E_{a_{2}} = 80 k J / m o l$
Step 3 $k_{3}$ $E_{a_{3}} = 50 k J / m o l$
And overall rate constant, $k = {(\frac{k_{1} k_{2}}{k_{3}})}^{2 / 3}$ .
The overall activation energy of the reaction will be:

A

140 k J / m o l

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

B

150 k J / m o l

No worries! We‘ve got your back. Try BYJU‘S free classes today!

C

130 k J / m o l

No worries! We‘ve got your back. Try BYJU‘S free classes today!

D

120 k J / m o l

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is A $140 k J / m o l$
$A e^{- E_{a} / R T} = {[\frac{A e^{- E_{a_{1}} / R T} \times A e^{- E_{a_{2}} / R T}}{A e^{- E_{a_{3}} / R T}}]}^{2 / 3}$
$= {[A e^{(- E_{a_{1}} - E_{a_{2}} + E_{a_{3}}) / R T}]}^{2 / 3}$
$E_{a} = \frac{2}{3} [E_{a_{1}} + E_{a_{2}} - E_{a_{3}}]$
$= \frac{2}{3} [180 + 80 - 50] = 140 k J / m o l$

Suggest Corrections

thumbs-up

3

Similar questions

Q. For a complex reaction

A K - \to P r o d u c t s, E_{a_{1}} = 180 K J / m o l e, E_{a_{2}} = 80 K J / m o l, E_{a_{3}} = 50 K J / m o l .

overall rate constant k is related to individual rate constant by the equation

k = {(\frac{K_{1} - K_{2}}{K_{3}})}^{2 / 3} .

Activation energy (KJ/mol) for the overall reaction is

Q. A reaction takes place in various steps. The rate constant for first, second, third and fifth steps are

k_{1}, k_{2}, k_{3}

k_{5}

respectively. The overall rate constant is given by,

k = \frac{k_{2}}{k_{3}} [\frac{k_{1}}{k_{5}}]^{1 / 2}

If activation energy is

40, 60, 50

10 k J / m o l

respectively, the overall energy of activation

(k J / m o l)

Q. For a reaction taking place in three steps, the rate constants are

k_{1}, k_{2}

k_{3}

. The overall rate constant

k = \frac{k_{1} k_{2}}{k_{3}}

. If the energy of activation values for the first, second and third stages are

40, 50

60

k J

{m o l}^{- 1}

respectively, then the overall energy of activation in

k J

{m o l}^{- 1}

Q. A reaction takes place in various steps. The rate constant for first, second, third and fifth steps are

k_{1}, k_{2}, k_{3}

k_{5}

respectively. The overall rate constant is given by

k = \frac{k_{2}}{k_{3}} {(\frac{k_{1}}{k_{5}})}^{1 / 2}

, if activation energy are

40, 60, 50

10

k J / m o l

respectively, the overall energy of activation (

k J / m o l

Q. A reactiontakes place in various steps. The rate constant for first, second, third and fifth steps are

k_{1}, k_{2}, k_{3}

k_{5}

respectively. The overall rate constant is given by:

k = \frac{k_{2}}{k_{3}} \times (\frac{k_{1}}{k_{5}})^{0.5}

If the activation energies are 40, 60, 50 and 10 kJ/mol respectively, the overall activation energy (kJ/mol) is:

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Arrhenius Equation

CHEMISTRY

Watch in App

explore_more_icon

Explore more

Arrhenius Equation

Standard XII Chemistry

Join BYJU'S Learning Program

CrossIcon