The total pressure of a mixture of H 2 and O 2 is 1.00 bar. The mixture is allowed to react to form water which is completely removed to leave only pure H 2 at a pressure of 0.35 bar. Assuming ideal gas behaviour and that all pressure measurements were made under the same conditions of temperature and volume. The mole fraction of H 2 in the original mixture is

Question

The total pressure of a mixture of H 2 and O 2 is 1.00 bar. The mixture is allowed to react to form water which is completely removed to leave only pure H 2 at a pressure of 0.35 bar. Assuming ideal gas behaviour and that all pressure measurements were made under the same conditions of temperature and volume. The mole fraction of H 2 in the original mixture is (A) 0.78 (B) 0.28 (C) 0.22 (D) 0.72

Tardigrade Admin · Accepted Answer

Let pressure of O 2 be ' x ' ∴ Pressure of H 2=1-x <img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/chemistry/3c7294c9c6704c1026e705617e45cbcf-.png" /> H 2 remaining =1-3 x =0.35 ∴ x =(0.65/3) XO2=0.217 ≃ 0.22 XH2=0.78

0.78

0.28

0.22

0.72

Let pressure of O2​ be ' x ' ∴ Pressure of H2​=1−x H2​ remaining =1−3x=0.35 ∴x=30.65​ XO2​​=0.217≃0.22 XH2​​=0.78

Let pressure of $O_{2}$ be ' $x$ '
$∴$ Pressure of $H_{2} = 1 - x$

$H_{2}$ remaining $= 1 - 3 x = 0.35$
$∴ x = \frac{0.65}{3}$
$X_{O_{2}} = 0.217 ≃ 0.22$
$X_{H_{2}} = 0.78$