Question

An environmental engineer is sampling the stack gas produced by a coal-burning power plant. The stack gas (a mixture of carbon dioxide, sulfur dioxide, and water) is pumped into a 20.0 liter cylinder at a pressure of 1.20 atm, and a temperature of 325 K. It is determined that the sample contains 0.315 mol of C02 and 0.494 mol of H20 a) How many moles of sulfur dioxide were present in the sample? b) What is the partial pressure (in atm) of sulfur dioxide in the stack gas? 5.17 The industrial production of lead from the mineral galena (lead (Il) sulfide) involves roasting the mineral with oxygen which produces sulfur dioxide and lead (II) oxide. How many liters of sulfur dioxide (measured at STP) will be produced by the reaction of 2.50 kg of galena with 152 L of oxygen gas at 493 K and 2.00 atm? 5.18 What is the ratio of effusion rates for the lightest and heaviest relatively-safe-to-inhale gasses, helium and sulfur hexafluoride? (Which makes your voice sound like Alvin the chipmunk and Barry White, respectively). 5.19 A sample of an unknown gas diffuses 4.668 times more slowly than a sample of hydrogen gas when tested under the same conditions. What is the molar mass of the unknown gas? 5.20

Answer 1

Volume of the gas mixture, V = 20.0l Pressure of gas mixture, P = 1.20 atm Temperature, T = 325K According to ideal gas equation, phivariant = nRT Total moles of the mixture, n_total = phivariant/RT (1.20 atm)(20.0L)/(0.0821 L atm K^-1. Mol^-1) (325 K) 0.899 mol No of moles of SO_2 - n_total - n_co_2 - n_H_2o 0.899 mol - 0.315 mol - 0.494 mol = 0.0900 mol Mole fraction contourintgeral_2, chi_co_2 = n_co_2/n_total = 0.0900 mol/0.899 mol = 0.1001 Partal pressure of the contourintgeral_2 gas, P_co_2 = (chi_CO_2) P_total (0.1001)(1.20atm) 0.120 atm