Question

Calculate the mass of 500ml of O2 at 27°C and 740mm of Hg

Answer 1

Using n = PV÷RT n=(740/760)0.5÷(0.0821×300) n=0.02 approx  Hence mass = moles × molecular mass  Mass of O2=0.02×32 =0.64g

Answer 2

The volume (V) occupied by n moles of any gas has a pressure (P) at temperature (T). The relationship for these variables will be,

PV = nRT, where R is the gas constant.

By applying the mathematical formula of ideal gas law or equation of state ,we get that.

n = PV/RT

=(740/760)0.5/(0.0821×300)

=0.02

So,

mass =number of moles × molecular mass O2=0.02×32

=0.64g (answer.)

So the answer will be 0.64 gm,by using the ideal gas law.