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The irreversible and second order reaction A2R+S is carried out in a plug flow reactor. The pressure of feed is 10atm at 800K and feed stream contains 70% reactant A and 30% inert by volume. The reactor of 0.2 L is isothermal, and the reaction occurs at 800K and pressure of 10atm. It is known that the outflow of the product R is 0.034mol/s and the conversion was 10%. Calculate the reaction rate constant if the reaction rate is rA=kCA2 (irreversible reactions at variable volume)