A gaseous compound is 30.4% nitrogen and 69.6% oxygen by mass.A 5.25-g sample of the gas occupies a volume of 1.00 L and exerts a pressure of 1.26 atm at -4.0°C.Which of these choices is its molecular formula? A)NO B)NO₂ C)N₃O₆ D)N₂O₄ E)N₂O₅

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Quizplus · Accepted Answer

The molar mass of the gas is:(5.25 g) / (1.00 L) * (273 K / (269.6 K)) * (1 atm / (1.26 atm)) = 46.0 g/molThe empirical formula of the gas is:N30.4% / 14.01 g/mol = 0.0217 mol NO69.6% / 16.00 g/mol = 0.0435 mol OThe empirical formula is NO2. The molecular formula is a multiple of the empirical formula. The molar mass of the molecular formula is 46.0 g/mol, so the molecular formula is N2O4.

A Gaseous Compound Is 30