The oxidation of nitric oxide 

takes place in an isothermal batch reactor. The reactor is charged with a mixture containing 20.0 volume percent NO and the balance air at an initial pressure of 380 kPa (absolute). 

(a) Assuming ideal-gas behavior, determine the composition of the mixture (component mole fractions) and the final pressure (kPa) if the conversion of NO is 90%. 

(b) Suppose the pressure in the reactor eventually equilibrates (levels out) at 360 kPa. What is the equilibrium percent conversion of NO? Calculate the reaction equilibrium constant at the prevailing temperature, K_p[(atm)^-0.5], defined as 

where p_i(atm) is the partial pressure of species i (NO₂, NO, O₂) at equilibrium. 

(c) Assuming that Kp depends only on temperature, estimate the final pressure and composition in the reactor if the feed ratio of NO to O₂ and the initial pressure are the same as in Part (a), but the feed to the reactor is pure O2 instead of air. 

(d) Replace the partial pressures in the expression for K_p, and use the result to explain how reactor pressure influences the conversion of NO to NO_2. 

Transcribed Image Text:

NO +02=NO,