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Standard XII

Chemistry

Types of Elementary Reactions

The substance...

Question

The substance undergoes first order decomposition. The decomposition follows two parallel first order reactions as given above.
If the corresponding activation energies of parallel reaction are 100 and 120 $k J m o l^{- 1}$ then the net activation energy of A is / are:

120 kJ mol

^{- 1}

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116 kJ mol

^{- 1}

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100 kJ mol

^{- 1}

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150 kJ mol

^{- 1}

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Solution

The correct option is C 116 kJ mol $^{- 1}$
The expression for the net activation energy is $E = \frac{k_{1} E_{1} + k_{2} E_{2}}{k_{1} + k_{2}}$
Substitute values in the above expression.
$E = \frac{10^{- 2} \times 100 + 120 \times 4 \times 10^{- 2}}{10^{- 2} + 4 \times 10^{- 2}} = 116 k J m o l^{- 1}$

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The substance undergoes first order decomposition. The decomposition follows two parallel first order reactions as given above.If the corresponding activation energies of parallel reaction are 100 and 120 kJ mol−1 then the net activation energy of A is / are:

The correct option is C 116 kJ mol−1The expression for the net activation energy is E=k1E1+k2E2k1+k2Substitute values in the above expression.E=10−2×100+120×4×10−210−2+4×10−2=116 kJ mol−1

The substance undergoes first order decomposition. The decomposition follows two parallel first order reactions as given above.
If the corresponding activation energies of parallel reaction are 100 and 120 $k J m o l^{- 1}$ then the net activation energy of A is / are: