Inorganic benzene reacts with HCl to form a compounds `B_(3)N_(3)H_(9)Cl_(3)`. The protonation occurs at:

Options

A. B-atom
B. N-atom
C. First at B-atom than rearranges into N-atom
D. first at N-atom then rearranges into B-atom

Explanation

To determine where protonation occurs in the reaction of inorganic benzene with HCl to form the compound \( B_3N_3H_9Cl_3 \), we can follow these steps:

### Step 1: Understand the Structure of Inorganic Benzene
Inorganic benzene, also known as borazine, has a cyclic structure composed of alternating boron (B) and nitrogen (N) atoms. The general structure can be represented as:

\[ \text{B}_3\text{N}_3\text{H}_9 \]

This means there are three boron atoms and three nitrogen atoms in a hexagonal ring, with hydrogen atoms attached to each atom.

### Step 2: Reaction with HCl
When inorganic benzene reacts with hydrochloric acid (HCl), the HCl can donate a proton (H⁺) to the molecule. The reaction can be visualized as follows:

\[ \text{B}_3\text{N}_3\text{H}_9 + 3 \text{HCl} \rightarrow \text{B}_3\text{N}_3\text{H}_9\text{Cl}_3 + 3 \text{H}^+ \]

### Step 3: Identify the Protonation Site
In the case of borazine, the nitrogen atoms are more basic than the boron atoms due to their higher electronegativity. This means that they are more likely to accept a proton.

- Each nitrogen atom has a lone pair of electrons that can be used to bond with a proton (H⁺).
- When HCl is added, the protons will preferentially attach to the nitrogen atoms.

### Step 4: Conclusion
The protonation occurs at the nitrogen atoms in the borazine structure. Therefore, the answer is that the protonation occurs at the nitrogen (N) atoms.

### Final Answer
The protonation occurs at the nitrogen (N) atoms.

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