For a reaction $A \to B$ , enthalpy of reaction is $- 4.2 k J m o l^{- 1}$ and enthalpy of activation is $9.6 k J m o l^{- 1}$ . The correct potential energy profile for the reaction is shown in option.

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Solution

The correct option is A
For the reaction,
$A \to B Δ H = - 4.2 k J m o l^{- 1}$
Thus, the reaction is exothermic.
Hence, energy of reactants are higher than the products.

Also, enthalpy of activation ( $E_{2}$ ) is approximately double of $Δ H$ of reaction.
Hence, for the given reaction energy profile (c) is correct.

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Similar questions

Q. For a reaction

A \to B

, enthalpy of reaction is

- 4.2 k J m o l^{- 1}

and enthalpy of activation is

9.6 k J m o l^{- 1}

. The correct potential energy profile for the reaction is shown in option.

In an exothermic reaction $A \to B$ , the activation energy of reverse reaction is twice that of forward reaction. If enthalpy of the reaction is -80 kJ $m o l^{- 1}$ , the activation energy of the reverse reaction is :

Q. The forward and backward activation energy of exothermic reaction

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Q. For a given reaction, energy of activation for forward reaction

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20 k J

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The energies of activation for forward and reverse reactions for $A_{2} + B_{2} ⇌ 2 A B$ are $180 k J m o l^{- 1}$ and $200 k J m o l^{- 1}$ respectively. The presence of a catalyst lowers activation energy of both reactions by $100 k J m o l^{- 1}$ . The enthalpy change of the reaction $(A_{2} + B_{2} \to 2 A B)$ in the presence of a catalyst will be (in kJ $m o l^{- 1}$ )

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For a reaction A→B, enthalpy of reaction is –4.2 kJ mol–1 and enthalpy of activation is 9.6 kJ mol–1. The correct potential energy profile for the reaction is shown in option.

The correct option is A For the reaction, A→B ΔH=−4.2 kJ mol−1 Thus, the reaction is exothermic. Hence, energy of reactants are higher than the products. Also, enthalpy of activation (E2) is approximately double of ΔH of reaction. Hence, for the given reaction energy profile (c) is correct.

For a reaction $A \to B$ , enthalpy of reaction is $- 4.2 k J m o l^{- 1}$ and enthalpy of activation is $9.6 k J m o l^{- 1}$ . The correct potential energy profile for the reaction is shown in option.