What will be the value of ΔH, if the forward and reverse reactions have the same energy of activation?
Correct Answer :
ΔH = 0
Solution :
The correct option is ΔH = 0.
To understand why this is the correct answer, let us look at the relationship between the enthalpy change () of a reaction and the activation energies of its forward and reverse paths.
For any chemical reaction, the change in enthalpy () is defined as the difference between the activation energy of the forward reaction () and the activation energy of the reverse reaction (). This can be mathematically expressed as:
According to the question, the forward and reverse reactions have the same energy of activation. Therefore, we can write:
Substituting this equality into the enthalpy change equation gives:
Consequently, the enthalpy change of the reaction is zero ().
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