Question

6. In a zinc blast furnace, zinc oxide and carbon are charged into a retort (essentially a closed vessel) and heated to a sufficient temperature (1100°C) such that the reaction ZnO (s) + C (s)-Zn (vapor) + CO(g) attains equilibrium a. b. c. Is the reaction endothermic or exothermic; i.e. does the process absorb heat or give off heat? If the system contains ZnO, C, CO, CO2 and Zn (vapor), how many phases are present? At 1100°C and at equilibrium the same species as in (b) are present. How many degrees of freedom does the system have? (Explain briefly how you arrive at your answer. i.e., show more of your work than just a single number) d. Would the number of degrees of freedom change if the process were carried out in the open atmosphere rather than in the retort? Why or why not? e. What does the phase rule tell us if Zn () begins to form in the retort at 1100°C along with ZnO, C, CO, CO2 and Zn (vapor):? Potentially useful data At 1373 K ZnO Zn (vapor) CO (g) AG [J/m] -196,230 0 -232,060 0 Afr, [Jin] -293,250 0 -114.200 0 55.5 20.8 34.0 22.6 AHfusion, Za7280 J/m at 693 K evaporation, Za 114.280 J/m at 1180 K

Answer 1

dothomi on 1