25 moles of `H_2` and 18 moles of `l_2` vapour were heated in a sealed tube at 445°C when at equilibrium 30.8 moles of HI were formed. Calculate the degree of dissociation of pure Hl at the given temperature,

Explanation

To solve the problem, we need to find the degree of dissociation of pure HI at the given temperature based on the equilibrium conditions provided. Here’s a step-by-step breakdown of the solution:

### Step 1: Write the balanced chemical equation
The reaction is:
\[ H_2(g) + I_2(g) \rightleftharpoons 2 HI(g) \]

### Step 2: Set up the initial moles
Initially, we have:
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