(Solved): 4.6 Zinc is to be purified by distillation (evaporation followed by condensation). (a) What is the ...

4.6 Zinc is to be purified by distillation (evaporation followed by condensation). (a) What is the level of vacuum (pressure) needed to distill zinc at $600^{?}\mathrm{C}(873$ $\mathrm{K})$ ? (b) How much energy in the form of heat (in joules per mole of zinc) is required for the distillation? Assume that the heat of condensation cannot be recovered because the zinc is condensed in a separate apparatus. DATA For zinc: $\ln P(\mathrm{atm})=?15,250+1.255\ln T(\mathrm{K})?21.79T(K)$