The vapour density of a mixture containing `NO_2` and `N_2O_4` is 38.3 at 27°C. Calculate the mole of `NO_(2)` in 100 g mixture.

Options

A. 0.437 mole
B. 0.7 mole
C. 0.37 mole
D. 0.27 mole

Answer

A

Explanation

Mol. wt. of mixture. of `NO_(2)` and `N_2O_4 = 38.3 xx 2 = 76.6`
Let a mole of `NO_2` be present in 100g mixture mole of `NO_2` + mole of `N_2O_4` = moles of mixture.
Total moles in mixture = `100/76.6 = 1.305`
wt. of `NO_2` + wt. of `N_2O_4` = wt. of mixture.
`a xx 46 + (1.305 -a) xx 92 = 100`
`a = 0.437` mole