Q. 565.0( 1 Vote )

50 cc of oxygen is collected in an inverted gas jar over water. The atmospheric pressure is 99.4 kPa and the room temperature is 27°C. The water level in the jar is same as the level outside. The saturation vapor pressure at 27°C is 3.4 kPa. Calculate the number of moles of oxygen collected in the jar.

Answer :


Volume of oxygen = 50cc=50cm3=50

Atmospheric pressure Po=99.4kPa=99.4Pa

Temperature =27=300.15K

Saturation vapor pressure Ps=3.4kPa=3.4Pa

According to question water level in the jar is same as level outside. So

Pressure inside the jar = pressure outside the jar

Pressure outside the jar =atmospheric pressure Po

Pressure inside the jar=Po …. (1)


Pressure inside the jar is also = vapor pressure of oxygen+ Saturation vapor pressure

Pressure inside the jar=P+Ps …. (2)

From equation (1) and (2), we can write



Applying ideal gas equation


Where V= volume of gas

R=gas constant =8.3JK-1mol-1


n=number of moles of gas

P=pressure of gas.

The number of moles of oxygen collected in the jar is 1.9310-3.

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Rotational Kinetic Energy43 mins
Colligative Properties {Theory}34 mins
Wheatstone Bridge - Theory Class35 mins
Electric Flux - Theory46 mins
Arrhenius equation & Collision Theory59 mins
Superfast Revision of Potential & Potenial Energy (Theory + Interactive Quiz)47 mins
Microsporogenesis & Megasporogenesis49 mins
NEET 2021 | Transcription - An important Topic62 mins
DNA Fingerprinting42 mins
Meselson and Stahl experiment49 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses