Enthalpy of neutralization of `HCl` by `NaOH` is `-57.1 J//mol` and by `NH_(4)OH` is `-51.1 KJ//mol`. Calculate the enthalpy of dissociation of `NH_(4)OH`.

Explanation

To calculate the enthalpy of dissociation of \( NH_4OH \), we can use the given enthalpy values for the neutralization reactions. Here is the step-by-step solution:

### Step 1: Write the reactions and their enthalpies
1. **Neutralization of HCl by NaOH:**
\[ HCl + NaOH \rightarrow NaCl + H_2O \quad \Delta H_1 = -57.1 \, \text{kJ/mol} \]

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