For a reaction `A rarr B, E_(a)` for the forward reaction `E_(a(f))` and backward reaction `E_(a(b))` is `9kJ mol^(-1)` and `9kJ mol^(-1)`, respectively. Potential energy of `A` is `12 kJ mol^(-1)`. Calculate
(a) The heat of the reaction
(b) The threshold energy of reaction `(THE)`

Explanation

To solve the given problem, we will follow these steps:

### Step 1: Understand the Data Given
We have the following data:
- Activation energy for the forward reaction, \( E_{a(f)} = 19 \, \text{kJ mol}^{-1} \)
- Activation energy for the backward reaction, \( E_{a(b)} = 9 \, \text{kJ mol}^{-1} \)
- Potential energy of reactant \( A \), \( PE_A = 12 \, \text{kJ mol}^{-1} \)

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