What will be the effect on reaction .
`N_2(g) +3H_2 hArr 2NH_3(g)`
by (i) compressing the volume to half
(ii) adding helium gas at constant pressure

Explanation

To solve the question regarding the effects on the reaction \( N_2(g) + 3H_2(g) \rightleftharpoons 2NH_3(g) \) under two different conditions, we will analyze each scenario step by step.

### Step 1: Analyzing the Effect of Compressing the Volume to Half

1. **Understanding the Reaction**: The balanced chemical equation shows that 1 mole of nitrogen gas (\(N_2\)) reacts with 3 moles of hydrogen gas (\(H_2\)) to produce 2 moles of ammonia gas (\(NH_3\)). Therefore, the total number of moles of gas on the reactant side is \(1 + 3 = 4\) moles, and on the product side, it is \(2\) moles.

2. **Effect of Volume Compression**: When the volume of the reaction vessel is compressed to half, the pressure of the gases increases. According to Boyle's Law, pressure is inversely proportional to volume. Thus, halving the volume will double the pressure.

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