A compound of phosphorus oxide has 43.6% of oxygen. Its empirical formula is?
Correct answer: B. P2O3
- A. P2O5
- B. P2O3
- C. P5O2
- D. PO2
Explanation
Let the total mass of the compound be 100g.Given that the percentage of oxygen is 43.6%. So, the mass of oxygen would also be 43.6g.Now, Mass of phosphorus = 100 - 43.6 = 56.4gNow, calculate the number of moles by dividing with molar masses. P : O 56.4/31 : 43.6/16 1.8 : 2.7 (Divide with smaller number to get a whole number.) 1.8/1.8 : 2.7/1.8 1.5 1(2): 1.5(2) (Divide with a suitable number to get a whole number)3Hence, the phosphorus oxide would be P₂O₃..
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Mole calculations connect mass, number of particles and Avogadro's number, while balanced equations provide the mole ratios used in stoichiometry. Questions cover limiting and excess reactants, theoretical yield and percentage yield, including identifying which reactant is consumed first and comparing the actual product with the maximum possible product.
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