A sample of charcoal weighing 0.6 g was brought into contact with a gas contained in a vessel of 100 mL capacity at 300 K. The pressure of the gas was found to fall from 70 torr to 40 torr. Calculate the volume of the gas (reduced to STP) that is adsorbed per gram of the adsorbent under the condition of the experiment. (Volume of the charcoal is negligible)

Initial                       Final p1=70 torr           p2=40 torr V1=100mL           V2=?T1=300K            T2=300K∴    p1V1T1=p2V2T2    V2=p1V1p2=7040×100=175mLVolume of the vessel = 100 mlL Volume of the gas adsorbed = 175-100 = 75 mL Volume of the gas adsorbed per gram of charcoal.=750.6=125 mL/gThis volume is reduced to STP Final  STP p2V2T2=p3V3T340×125300=760×V3273∴V3( at STP )=40×125×273300×760=6.0mL