Question

Determine the number of moles of each gas present in a mixture of CH4 and C2H6 in a 2.00-L vessel at 25°C and 1.72 atm, given that the partial pressure of CH4 is 0.45 atm. What is the number of moles of CH4? mol What is the number of moles of C2H6? mol

Answer 1

Total no of mole of mixer (n) = PV/RT

                                                    = 1.72*2/(0.0821*298)

                                                      = 0.14 mole

partial pressure of CH4 = Xch4*Ptotal

                      0.45 = nCH4/nTotal * Ptotal

                    0.45 = x/0.14*1.72

x = number of moles of CH4 = 0.037 mole

number of moles of C2H6 = 0.14 - 0.037 = 0.103 mole