Styrene can be made by catalytic dehydrogenation of ethyl benzene. The reaction is usually carried out in the presence of steam, which acts as a heat carrier and reduces coking on the catalyst. If a mixture of steam and ethyl benzene is fed to an adiabatic reactor at 2 bar, 640 °C, estimate the equilibrium conversion and outlet temperature as a function of the ratio of steam to ethyl benzene. What ratio would you recommend using in practice?