Part b an "empty" container is not really empty if it contains air. how may moles of nitrogen are in an "empty" two-liter cola bottle at atmospheric pressure and room temperature (25∘c)? assume ideal behavior. express your answer to three significant figures and include the appropriate units.

6.38x10^-2 moles
       First, let's determine how many moles of gas particles are in the two-liter container. The molar volume for 1 mole at 25C and 1 atmosphere is 24.465 liters/mole. So
   2 L / 24.465 L/mol = 0.081749438 mol
       Now air doesn't just consist of nitrogen. It also has oxygen, carbon dioxide, argon, water vapor, etc. and the total number of moles includes all of those other gasses. So let's multiply by the percentage of nitrogen in the atmosphere which is 78%
    0.081749438 mol * 0.78 = 0.063764562 mol.
        Rounding to 3 significant figures gives 6.38x10^-2 moles

They are all solids.