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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