Some data need to be converted to its standard units; i.e.,
#P=Pressure=752cancel("torr")xx(1atm)/(760cancel("torr"))=0.989atm#
#T=Temperature=24^oC+273=297K#
Now, find the number of moles #(eta)# of #O_2# at the given atmospheric condition as described in the problem above . Use the formula shown below. Rearrange to isolate the unknown variable, #eta# and plug in values; i.e.,
#PV=etaRT#
#eta=(PV)/(RT)#
#where:#
#V="Volume"=155L" of "O_2#
#R="Gas Constant"=(0.08205L*atm)/(mol*K)#
#P="Pressure"=0.989atm#
#T="Temperature"=297K#
#eta=(PV)/(RT)#
#eta=((0.989cancel(atm))(155cancel(L)))/(((0.08205cancel(L*atm))/(mol*K))(297K)#
#eta=6.29molO_2#
Then, find the mole of #NO_2#. Refer to the balanced equation for the mole ratio.
#=6.29cancel(molO_2)xx(2molNO_2)/(1cancel(molO_2))#
#=12.6molNO_2#
Since the conditions of these two gases, the #O_2# and #NO_2# are the same; then, the relationship that #6.29molO_2-=155L*O_2# is also equal to the relationship #6.29molNO_2-=155L*NO_2# and can be used to find the volume of #NO_2# gas; i.e.,
#=12.6cancel(molNO_2)xx(155LNO_2)/(6.29cancel(molNO_2))#
#=310L*NO_2#
