`20%N_(2)O_(4)` molecules are dissociated in a sample of gas at `27^(@)C` and 760 torr. Calculate the density of the equilibrium mixture.

Explanation

`{:(,N_(2)O_(4)hArr,2NO_(2),,),("Mole presentinitially",1,0,,),("Mole at Eq",(1-0.2),0.4,,):}`
`:.` M. wt. of mixture `= (0.8 xx 92 +0.4 xx 46)/(1.2) =76.66`
Now `PV =(w)/(m)RT`
or `(w)/(V) = (Pm)/(RT) = (76.66 xx 1)/(0.082 xx 300) = 3.116 g litre^(-1)` .