`LiH + B_2 H_6 overset("dry ether")to X`
In this reaction 'X' is used as

Options

A. Oxidising agent
B. Reducing agent
C. Flux for soldering metals
D. Mild antiseptic

Answer

To solve the question regarding the reaction of lithium hydride (LiH) with diborane (B₂H₆) in the presence of dry ether, we can follow these steps:

### Step 1: Identify the Reactants
The reactants in this reaction are lithium hydride (LiH) and diborane (B₂H₆).

### Step 2: Understand the Reaction Conditions
The reaction occurs in the presence of dry ether, which is a solvent that helps facilitate the reaction between LiH and B₂H₆.

### Step 3: Write the Reaction Equation
When lithium hydride reacts with diborane, the reaction can be represented as follows:

\[ 2 \text{LiH} + \text{B}_2\text{H}_6 \rightarrow 2 \text{LiBH}_4 \]

### Step 4: Identify the Product
The product formed from this reaction is lithium borohydride (LiBH₄).

### Step 5: Determine the Use of the Product
Lithium borohydride (LiBH₄) is commonly used as a reducing agent in various chemical reactions.

### Conclusion
Thus, in this reaction, 'X' is lithium borohydride (LiBH₄), which is used as a reducing agent.

### Final Answer
X = Lithium borohydride (LiBH₄), used as a reducing agent.

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