Consider the process shown in the figure. A bulk gas stream containing 0.10 mole% of carbon monoxide (CO) gas, 2.0 mole% O₂gas, and 97.9 mole% of CO₂gas flows over a flat catalytic surface of length 0.50 m at a bulk velocity of 40 m/s at 1.0 atm and 600 K. Heat-transfer processes maintain the gas stream and catalytic surface at 600 K. At this temperature, the catalytic surface promotes the oxidation reaction CO(g) + 1/2O₂(g) †’ CO₂(g). Let A = CO, B = O₂, C = CO₂. The gas-phase diffusion coefficients at 1.0 atm and 300 K are D_AB= 0.213 cm²/s, D_AC= 0.155 cm²/s, D_BC = 0.166 cm²/s. 

a. What are the Schmidt numbers for CO and O₂ mass transfer? What species (CO, O₂, CO₂) is considered the carrier gas? 

b. For CO mass transfer, what is the average convective mass- transfer coefficient (k_c) over the 0.50 m length of the catalytic surface, and the local mass transfer coefficient (k_c,x) at the far edge of the catalytic surface (x = L = 0.50 m)? 

c. Using boundary-layer theory, scale k_c for CO mass transfer to k_c for O₂ transfer. 

d. At 600 K, the surface reaction constant for the first-order oxidation reaction with respect to CO concentration is k_s = 1.5 cm/s. What is the average molar flux of CO to the catalytic surface, assuming that the composition of CO in the bulk gas is maintained at 0.10 mole%?

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600 K, 1.0 atm V= 40 m/s 0.1 mole% CO 2.0 mole% O2 97.9 mole% CO2 CO(A) + 1/20,(B) CO2 (C) Сдя NA CAs catalyst surface X = L = 0.5 m