Concept:A balanced chemical equation provides the molar ratio, which can be converted into a mass ratio using the molar masses of the specific reactants.
Formula:$$ \text{Mass Ratio} = m(\text{H}_2) : m(\text{Cl}_2) $$
Solution:- From the given balanced equation: 1 mole of \( \text{H}_2 \) reacts with 1 mole of \( \text{Cl}_2 \).
- Mass of 1 mole of \( \text{H}_2 = 2 \times 1 = 2 \text{ g} \).
- Mass of 1 mole of \( \text{Cl}_2 = 2 \times 35.5 = 71 \text{ g} \).
- The mass ratio is therefore \( 2 : 71 \).
- Simplifying this ratio by dividing both sides by 2 yields: \( 1 : 35.5 \).
Why other options are incorrect:- 2 : 35.5: Fails to account for the diatomic nature of chlorine gas (\( \text{Cl}_2 \)) in the mass calculation.
- 1 : 71: Mathematically incorrect simplification of \( 2:71 \).
- 2 : 70: Uses an incorrect atomic mass for Chlorine.
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