An oxygen cylinder of volume 30 litre has 18.20 moles of oxygen. After some oxygen is withdrawn from the cylinder, its gauge pressure drops to 11 atmospheric pressure at temperature . The mass of the oxygen withdrawn from the cylinder is nearly equal to [

STUDY MATERIALS
COURSES
MORE
SUCCESS STORY
ADMISSION
STORE

Back

JEE ADVANCE

CLASS XI - XII
CRASH COURSE

CLASS XI - XII

CRASH COURSE

JEE MAIN

CLASS XI - XII
CRASH COURSE

CLASS XI - XII

CRASH COURSE

NEET

CLASS XI - XII
CRASH COURSE

CLASS XI - XII

CRASH COURSE

BITSAT

CLASS XI - XII

CLASS XI - XII

CBSE BOARD

CLASS IX

CLASS X

CLASS XI

CLASS XII

CLASS VI

CLASS VII

CLASS VIII

UP BOARD

CLASS IX
CLASS X
CLASS XI
CLASS XII

CLASS IX

CLASS X

CLASS XI

CLASS XII

CUET

CRASH COURSE

CRASH COURSE

Courses

CLASSROOM COURSES
ONLINE COURSES

ONLINE COURSES

More

Solution

Q.
An oxygen cylinder of volume 30 litre has 18.20 moles of oxygen. After some oxygen is withdrawn from the cylinder, its gauge pressure drops to 11 atmospheric pressure at temperature $27 ° C$ . The mass of the oxygen withdrawn from the cylinder is nearly equal to

$[Given, R = \frac{100}{12} {J mol}^{- 1} K^{- 1}, and molecular mass of O_{2} = 32, 1 atm pressure = 1.01 \times 10^{5} N/m]$ [2025]

1 0.116 kg

2 0.156 kg

3 0.125 kg

4 0.144 kg

Ans.
(1)

Initially volume of the oxygen cylinder,

$V_{1} = 30 L = 30 \times 10^{- 3} m^{3}$

Number of moles, $n_{1} = 18.20$

   $T_{1} = 27 + 273 = 300$ $K$

Final gauge pressure, $P_{g} = 11$ $atm$

Final absolute pressure, $P_{2} = P_{g} + P_{a t m} = 11 + 1 = 12$ $atm$

For oxygen, molecular weight, $M = 32$ $g$

Initial mass of oxygen in the cylinder,

   $m_{1} = n_{1} M = 18.20 \times 32 = 582.4$ $g$

Now, $V_{2} = 30 \times 10^{- 3} m^{3},$ $P_{2} = 12 \times 1.01 \times 10^{5} Pa$

   $n_{2} = \frac{P_{2} V_{2}}{R T_{2}} = \frac{(12 \times 1.01 \times 10^{5}) \times (30 \times 10^{- 3})}{8.3 \times 300} = 14.60$

$∴$ Final mass of oxygen gas in the cylinder,

   $m_{2} = 14.60 \times 32 = 467.2$ $g$

$∴$ Mass of the withdrawn oxygen gas

   $= m_{1} - m_{2} = 582.4 - 467.2 = 115.2 g \approx 0.116 kg$

Want Us to Email you About Special Offers & Updates?