Diborane is prepared on large scale by

Options

A. `2BF_(3(g)) + 6LiH_((s)) overset(450 K)rarr B_(2) H_(6(g))+ 6LiF_((s))`
B. `2BCI_(3(g))+ 6LiH_((s)) overset(450 K)rarr B_(2)H_(6(g)) + 6LiCl_((s))`
C. `2BF_(3(g))+6NaH overset(450 K)rarr B_(2)H_(6) + 6NaF`
D. `2BCI_(3) + 6NaH overset(450 K)rarr B_(2)H_(6) + 6NaCI`

Answer

To prepare diborane on a large scale, we need to analyze the reactants and their stability. The most common method for the large-scale preparation of diborane (B2H6) is through the reaction of boron trichloride (BCl3) with lithium hydride (LiH). Here’s a step-by-step breakdown of the process:

### Step 1: Identify the Reactants
The two key reactants for the preparation of diborane are:
- Boron trichloride (BCl3)
- Lithium hydride (LiH)

### Step 2: Analyze the Stability of Reactants
To ensure a high yield of diborane, we need to choose less stable reactants.
- **Boron Trichloride (BCl3)** is less stable compared to Boron Trifluoride (BF3) because BF3 has pπ-pπ back bonding, which stabilizes it. Therefore, BCl3 is preferred as it will react more readily to form diborane.
- **Lithium Hydride (LiH)** is more stable than Sodium Hydride (NaH) due to stronger ionic interactions. However, we need a less stable hydride for better reaction completion, so we will use Sodium Hydride (NaH) instead.

### Step 3: Write the Reaction Equation
The reaction between BCl3 and NaH can be represented as follows:
\[ 2 BCl_3 + 6 NaH \rightarrow B_2H_6 + 6 NaCl \]

### Step 4: Conclusion
Thus, the large-scale preparation of diborane is effectively achieved by the reaction of boron trichloride (BCl3) with sodium hydride (NaH).

### Final Answer
Diborane is prepared on a large scale by the reaction of **BCl3 with NaH**.

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