Select the incorrect statement about the boron.

Options

A. Pure form of the elements are obtained by the reduction of `BCl_(3)` with zinc at `900^(@)C`.
B. Crystalline boron is attacked only by hot concentrated oxidising agents.
C. Amorphous boron and ammonia at white gives `(BN)_(x)`, a slippery white solid with a layer structure resembling that of graphite.
D. Boron does form `B^(3+)` cation easily.

Explanation

To determine the incorrect statement about boron, we will evaluate each of the provided statements step by step.

### Step 1: Evaluate Statement 1
**Statement:** Pure boron of the elements are obtained by reduction of boron chloride with zinc at 900 degrees Celsius.

**Analysis:** This statement is true. When boron trichloride (BCl3) is heated with zinc (Zn) at elevated temperatures (around 900°C), zinc acts as a reducing agent. The reaction can be represented as:
\[ 2 \text{BCl}_3 + 3 \text{Zn} \rightarrow 2 \text{B} + 3 \text{ZnCl}_2 \]
This confirms that pure boron can indeed be obtained through this method.

### Step 2: Evaluate Statement 2
**Statement:** Crystalline boron is attacked by hot concentrated oxidizing agents.

**Analysis:** This statement is also true. Crystalline boron reacts with strong oxidizing agents such as concentrated sulfuric acid (H2SO4) or concentrated nitric acid (HNO3), leading to the formation of boric acid (H3BO3) or boron oxide (B2O3). Thus, this statement is correct.

### Step 3: Evaluate Statement 3
**Statement:** Amorphous boron and ammonia give a white crystalline slippery substance called BNX, known as inorganic graphite.

**Analysis:** This statement is true. Amorphous boron reacts with ammonia (NH3) to form boron nitride (BN), which has a layered structure similar to graphite, hence referred to as inorganic graphite. The reaction can be summarized as:
\[ \text{B} + \text{NH}_3 \rightarrow \text{BN} + \text{H}_2 \]
This confirms that this statement is accurate.

### Step 4: Evaluate Statement 4
**Statement:** Boron does form B3+ cation easily.

**Analysis:** This statement is incorrect. While boron can lose electrons to form cations, the formation of B3+ is not easy due to high ionization energies. The electronic configuration of boron is \(1s^2 2s^2 2p^1\). The first ionization energy is relatively low, but the second and third ionization energies are significantly higher due to the stability of the remaining electron configuration. Thus, the formation of B3+ is difficult because it requires overcoming these high ionization energies.

### Conclusion
Based on the evaluations of the statements, the incorrect statement about boron is:

**Answer:** Option 4: Boron does form B3+ cation easily.

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