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
