Easy MCQ +4 / -1 PYQ · JEE Mains 2021

Complete combustion of 1.80 g of an oxygen containing compound (CxHyOz) gave 2.64 g of CO2 and 1.08 g of H2O. The percentage of oxygen in the organic compound is :

  1. A 51.63
  2. B 50.33
  3. C 63.53
  4. D 53.33 Correct answer

Solution

C<sub>x</sub>H<sub>y</sub>O<sub>z</sub> + O<sub>2</sub> $\to$ xCO<sub>2</sub> + ${y \over 2}{H_2}O$ <br><br>2.64 g of CO<sub>2</sub> contains 0.72 g C. <br><br>1.08 g of H<sub>2</sub>O contains 0.12 g H. <br><br>$\therefore$ Mass of oxygen present = 1.80 – (0.72 +0.12) = 0.96 g <br><br>% of O = ${{0.96} \over {1.80}} \times 100$ = 53.33 %

About this question

Subject: Chemistry · Chapter: Some Basic Concepts of Chemistry · Topic: Mole Concept

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