Medium INTEGER +4 / -1 PYQ · JEE Mains 2021

100 g of propane is completely reacted with 1000 g of oxygen. The mole fraction of carbon dioxide in the resulting mixture is x $\times$ 10$-$2. The value of x is ____________. (Nearest integer)

[Atomic weight : H = 1.008; C = 12.00; O = 16.00]

Answer (integer) 19

Solution

C<sub>3</sub>H<sub>8(g)</sub> + 5O<sub>2(g)</sub> $\to$ 3CO<sub>2(g)</sub> + 4H<sub>2</sub>O<sub>(l)</sub><br><br><table> <thead> <tr> <th>t = 0</th> <th>2.27 mole</th> <th>31.25 mol</th> <th></th> <th></th> </tr> </thead> <tbody> <tr> <td>t = $\infty$</td> <td>0</td> <td>19.9 mol</td> <td>6.81 mol</td> <td>9.08 mol</td> </tr> </tbody> </table><br><br>mole fraction of CO<sub>2</sub> in the final reaction mixture (heterogenous)<br><br>${X_{C{O_2}}} = {{6.81} \over {19.9 + 6.81 + 9.08}}$<br><br>= 0.1902 = 19.02 $\times$ 10<sup>$-$2</sup><br><br>$\Rightarrow$ 19

About this question

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

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