How is lithium aluminium hydride prepared? What is its important use?

Explanation

**Step-by-Step Text Solution:**

**Step 1: Preparation of Lithium Aluminium Hydride (LiAlH4)**
Lithium aluminium hydride is prepared through a chemical reaction involving lithium hydride (LiH) and aluminium chloride (AlCl3). The balanced chemical equation for this reaction is:

\[ 4 \text{LiH} + \text{AlCl}_3 \rightarrow \text{LiAlH}_4 + 3 \text{LiCl} \]

In this reaction, four moles of lithium hydride react with one mole of aluminium chloride to produce one mole of lithium aluminium hydride and three moles of lithium chloride.
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