The heat of neutralisation will be highest for which of the following neutralisation reactions?

Options

A. `NH_4OH and HCl`
B. `NH_4OH and CH_3COOH`
C. `NaOH and HCl`
D. `NaOH and CH_3COOH`

Answer

To determine which neutralization reaction has the highest heat of neutralization, we need to consider the nature of the acids and bases involved in each reaction. Here’s a step-by-step solution:

### Step 1: Understand Heat of Neutralization
The heat of neutralization is defined as the amount of heat released when an acid reacts with a base to form water and a salt. This process is exothermic, meaning it releases heat.

### Step 2: Identify Strong and Weak Acids/Bases
- **Strong Acids**: Completely ionize in solution (e.g., HCl, HNO3).
- **Strong Bases**: Completely dissociate in solution (e.g., NaOH, KOH).
- **Weak Acids**: Partially ionize in solution (e.g., CH3COOH).
- **Weak Bases**: Partially dissociate in solution (e.g., NH4OH).

### Step 3: Compare Different Reactions
The heat of neutralization is generally higher for reactions involving strong acids and strong bases compared to weak acids and weak bases. This is because weak acids and bases require additional energy to ionize, which reduces the overall heat released during the reaction.

### Step 4: Analyze Given Options
Assuming the options provided in the question include combinations of strong and weak acids/bases, we should identify which combination involves a strong acid and a strong base.

### Step 5: Conclusion
Among the given options, the reaction between a strong acid (like HCl) and a strong base (like NaOH) will yield the highest heat of neutralization. Therefore, the correct answer is the reaction involving HCl and NaOH.

### Final Answer
The heat of neutralization will be highest for the reaction between HCl (strong acid) and NaOH (strong base).