Q. Calculate the total pressure in a 10.0 L cylinder which contains 0.4 g helium, 1.6 g oxygen and 1.4 g nitrogen at $27℃$
A) 0.492 atm
B) 49.2 atm
C) 4.92 atm
D) 0.0492 atm
Explanation
(a)
Number of moles of helium $= \frac{0.4}{4} = 0.1$
Number of moles of oxygen $= \frac{1.6}{32} = 0.05$
Number of moles of nitrogen $= \frac{1.4}{28} = 0.05$
Total moles in the 10.0 L cylinder at $27℃$
$= (0.1 + 0.05 + 0.05)$
$= 0.2\$mol
$p_{T} = \frac{nRT}{V} = \frac{0.2 \times 0.082 \times 300}{10} = 0.492\ atm$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.