The change in the enthalpy of `NaOH+HCl rarr NaCl+H_(2)O` is called :

Options

A. Heat of neutralisation
B. Heat of reaction
C. Heat of hydration
D. Heat of solution

Answer

To determine the change in enthalpy for the reaction of sodium hydroxide (NaOH) with hydrochloric acid (HCl) to form sodium chloride (NaCl) and water (H₂O), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reaction**:
The given reaction is:
\[ \text{NaOH} + \text{HCl} \rightarrow \text{NaCl} + \text{H}_2\text{O} \]

2. **Classify the Reaction**:
This reaction involves a strong base (NaOH) reacting with a strong acid (HCl). When an acid reacts with a base, it typically results in the formation of a salt and water.

3. **Define the Type of Reaction**:
The reaction between an acid and a base is known as a **neutralization reaction**.

4. **Understand Enthalpy Change**:
The change in enthalpy (ΔH) that occurs during this reaction is specifically related to the energy released or absorbed when the acid and base react to form the salt and water.

5. **Identify the Specific Enthalpy Change**:
The enthalpy change associated with a neutralization reaction is referred to as the **heat of neutralization**.

6. **Conclusion**:
Therefore, the change in enthalpy for the reaction of NaOH with HCl is called the **heat of neutralization**.

### Final Answer:
The change in the enthalpy of the reaction \( \text{NaOH} + \text{HCl} \rightarrow \text{NaCl} + \text{H}_2\text{O} \) is called the **heat of neutralization**.

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