Question #90bc3

1 Answer
Jun 9, 2017

Given

Volume of nitrogen #V=82.1mL=0.0821L#

Pressure of the gas collected excluding aqueous tension

#P=(774.5-14.5)mm=760/760=1atm#

Temperature of the gas #T=(27+273)=300K#

Universal gas constant #R=0.0821LatmK^-1mol^-1#

Let mass of the gas be #w# g

Molar mass of the gas #M=2xx14=28g"/"mol#

So applying Ideal gas equation

#PV=w/MRT#

#=>w=(PVM)/(RT)#

#=>w=(1xx0.0821xx28)/(0.0821xx300)=28/300g#

So percentage of nitrogen in the compound

#=(28/300)/0.14xx100=66.7%#