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Chemistry · Some Basic Concepts of Chemistry
हिन्दीIn the reaction \( \text{P}_4(\text{s}) + 5\text{O}_2(\text{g}) \rightarrow \text{P}_4\text{O}_{10}(\text{s}) \), if \( 1.24\text{ g} \) of phosphorus (\( \text{P}_4 \)) is reacted with \( 1.60\text{ g} \) of oxygen (\( \text{O}_2 \)), the mass of \( \text{P}_4\text{O}_{10} \) formed and the unreacted reactant are respectively: (Atomic masses: \( \text{P} = 31\text{ u} \), \( \text{O} = 16\text{ u} \))
Correct answer · Option 1
\( 2.84\text{ g} \), no reactant remains
Explanation
Moles of \( \text{P}_4 = 1.24 / 124 = 0.010\text{ mol} \); moles of \( \text{O}_2 = 1.60 / 32 = 0.050\text{ mol} \). For \( 0.050\text{ mol} \) \( \text{O}_2 \), required \( \text{P}_4 = 0.050 / 5 = 0.010\text{ mol} \). Thus, both reactants are present in exact stoichiometric proportions! Mass of \( \text{P}_4\text{O}_{10} = 0.010 \times 284 = 2.84\text{ g} \).
