The irreversible gas-phase reaction A +B C + D is carried out in an isothermal packed bed reactor. The feed is equimolar, with CA0 = CB0 = 2 mol/L. The initial volumetric flow rate is 4 L/s. The reaction is first order with respect to A and first order with respect to B, and the rate constant is 0.01 L2kg-1 mol-1 s-1. The pressure drop parameter, , is 0.0015 kg-1. If 400 kg of catalyst are used in the reactor, what is the percent conversion of A, expressed to one decimal place?