66) V1 = V2 = 1.00 L          gas1 = N2          gas2 = CH4          T = 273 K          P = 1 atm      

      (a) Each volume would contain the same number of gas molecules because Avogadro's hypothesis states that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules.

      (b) D(N2) > D(CH4) because the MM(N2) = 28.02 g and the MM(CH4) = 16.05 g

      (c) The KEave for both gases would be the same because they are at the same temperature.

      (d) r1/r2 = (m2/m1)1/2

            r(N2)/r(CH4) = (MM(CH4)/MM(N2))1/2

            The rate of effusion for CH4 would be greater than that of N2 because it has a smaller molar mass.