A gas mixture with a molar analysis of 20% C3H8 (propane) and 80% air enters a control volume operating at steady state at location 1 with a mass flow rate of 5 kg/min, as shown in Fig. P12.10. Air enters as a separate stream at 2 and dilutes the mixture. A single stream exits with a mole fraction of propane of 3%. Assuming air has a molar analysis of 21% O2 and 79% N2, determine

(a) The molar flow rate of the entering air at 2, in kmol / min

(b) The mass flow rate of oxygen in the exiting stream, in kg / min.