Assertion : Anilinium choride is more acidic than ammonium chloride.
Reason : Anilinium ion is resonance-stabilised.

Options

A. if both Assertion and Reason are true and reason is the correct explanation of the assertion.
B. if both assertion and reason are true but reason is not the correct expalanation of the assertion
C. if assertion is true, reason is false
D. both assertion and reason are false statements.

Explanation

To solve the question regarding the assertion and reason about anilinium chloride and ammonium chloride, we can follow these steps:

### Step 1: Understand the Compounds
- **Anilinium chloride** (C6H5NH3Cl) is the salt formed from aniline (C6H5NH2) and hydrochloric acid (HCl).
- **Ammonium chloride** (NH4Cl) is the salt formed from ammonia (NH3) and hydrochloric acid (HCl).

### Step 2: Compare Acidity
- Acidity can be understood in terms of the stability of the conjugate acid formed after protonation.
- The anilinium ion (C6H5NH3+) is formed when aniline accepts a proton (H+), while the ammonium ion (NH4+) is formed when ammonia accepts a proton.

### Step 3: Analyze Basicity of Aniline and Ammonia
- Aniline has a lone pair of electrons on the nitrogen atom, which can participate in resonance with the aromatic ring. This resonance delocalizes the lone pair, making it less available to accept protons, thus making aniline a weaker base compared to ammonia.
- Ammonia, on the other hand, does not have such resonance stabilization, and its lone pair is more available for protonation.

### Step 4: Conclusion on Acidity
- Since aniline is less basic than ammonia, the conjugate acid (anilinium ion) is more stable than the conjugate acid of ammonia (ammonium ion). Therefore, anilinium chloride is more acidic than ammonium chloride.

### Step 5: Evaluate the Assertion and Reason
- **Assertion**: "Anilinium chloride is more acidic than ammonium chloride." - This is **true**.
- **Reason**: "Anilinium ion is resonance-stabilized." - This is **false** because while the anilinium ion can be formed from aniline, it is not resonance-stabilized in the same way as the aniline itself is. The lone pair is not available for resonance after protonation.

### Final Answer
- The assertion is correct, but the reason is incorrect. Thus, the correct option is that the assertion is true and the reason is false.

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