Concept:The balanced chemical equation dictates the exact molar ratio between reactants and products. We must first identify if there is a limiting reactant.
Formula:$$ 2\text{H}_2 + \text{O}_2 \rightarrow 2\text{H}_2\text{O} $$
Solution:- From the balanced equation: 2 moles of \( \text{H}_2 \) react with 1 mole of \( \text{O}_2 \) to produce 2 moles of \( \text{H}_2\text{O} \).
- We are given 4 moles of \( \text{H}_2 \) and 2 moles of \( \text{O}_2 \).
- The ratio of available \( \text{H}_2 \) to \( \text{O}_2 \) is \( 4:2 \), which perfectly simplifies to the stoichiometric \( 2:1 \) ratio.
- Since neither reactant is in excess, they will completely react. 4 moles of \( \text{H}_2 \) will produce exactly 4 moles of \( \text{H}_2\text{O} \).
Why other options are incorrect:- Five / Six / Three: These violate the fundamental stoichiometric ratios established by the balanced chemical equation.
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