4 mol HO (1) 25C In the flow diagram on the right, 4 mol of pure...

 

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4 mol H₂O (1) 25°C In the flow diagram on the right, 4 mol of pure water 25°C and 100 mol of dry air (79 1 atm mol % N₂, 21 mol % O₂) at 25°C and 1 atm are placed 1 atm in an electric evaporator. Humid air (n₁) and some liquid water (n₂) at 100°C and 2 atm are removed from the evaporator. Some of the N₂ and O₂ dissolves in the water. Based on this information, answer the following: Q (kJ) W (kJ) 100 mol dry air 0.79 mol N, (g)/mol 0.21 mol O₂ (g)/mol n, mol humid air y, mol N, (g)/mol Evaporatory, mol O₂ (g)/mol 1-y,-y₂ H₂O (v)/mol 100°C 2 atm n, mol liquid x, mol N₂ (1)/mol x₂ mol O₂ (1)/mol 1-x,-x, mol H₂O (1)/mol 100°C 2 atm a) (6 pts) Perform degree-of-freedom analysis required to solve for all unknowns. Justify each number in the analysis (e.g. specify the unknowns, identify but do not write out the equations). b) (12 pts) Write all independent equations and material balances that could be used to solve for the unknowns. Do not write the energy balance. Specify what each equation represents (e.g. total mole balance). If you use Raoult's law or Henry's law, provide a term representing the vapor pressure (e.g. p*H20(50°C)) or Henry's law constant (Ho2(50°C)). Do not perform any calculations. c) (6 pts) When determining the vapor pressure of water at 50°C, what is the percent error if you use the Antoine equation instead of Table B.3? Percent error can be calculated as Ip* Antoine - P*table/P*table x 100%. d) (6 pts) Simplify the general energy balance assuming that the evaporator is a fixed- volume, insulated container. Justify which terms should be crossed off and which should be maintained. e) (6 pts + 2 pts EC) Using the enthalpy tables in the back of the book, what are the specific internal energy values for (i) the liquid water entering the process (in kJ/kg) and (ii) the dry air exiting the process (in kJ/mol)? Assume that the dry air behaves as an ideal gas and ignore the contribution of pressure. Which table(s) did you use, and what is the reference state for each table? 4 mol H₂O (1) 25°C In the flow diagram on the right, 4 mol of pure water 25°C and 100 mol of dry air (79 1 atm mol % N₂, 21 mol % O₂) at 25°C and 1 atm are placed 1 atm in an electric evaporator. Humid air (n₁) and some liquid water (n₂) at 100°C and 2 atm are removed from the evaporator. Some of the N₂ and O₂ dissolves in the water. Based on this information, answer the following: Q (kJ) W (kJ) 100 mol dry air 0.79 mol N, (g)/mol 0.21 mol O₂ (g)/mol n, mol humid air y, mol N, (g)/mol Evaporatory, mol O₂ (g)/mol 1-y,-y₂ H₂O (v)/mol 100°C 2 atm n, mol liquid x, mol N₂ (1)/mol x₂ mol O₂ (1)/mol 1-x,-x, mol H₂O (1)/mol 100°C 2 atm a) (6 pts) Perform degree-of-freedom analysis required to solve for all unknowns. Justify each number in the analysis (e.g. specify the unknowns, identify but do not write out the equations). b) (12 pts) Write all independent equations and material balances that could be used to solve for the unknowns. Do not write the energy balance. Specify what each equation represents (e.g. total mole balance). If you use Raoult's law or Henry's law, provide a term representing the vapor pressure (e.g. p*H20(50°C)) or Henry's law constant (Ho2(50°C)). Do not perform any calculations. c) (6 pts) When determining the vapor pressure of water at 50°C, what is the percent error if you use the Antoine equation instead of Table B.3? Percent error can be calculated as Ip* Antoine - P*table/P*table x 100%. d) (6 pts) Simplify the general energy balance assuming that the evaporator is a fixed- volume, insulated container. Justify which terms should be crossed off and which should be maintained. e) (6 pts + 2 pts EC) Using the enthalpy tables in the back of the book, what are the specific internal energy values for (i) the liquid water entering the process (in kJ/kg) and (ii) the dry air exiting the process (in kJ/mol)? Assume that the dry air behaves as an ideal gas and ignore the contribution of pressure. Which table(s) did you use, and what is the reference state for each table?

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Answer From Perry chemical engineers handbook H for combustion of methane is 882 KJmol A methane is at 25C Air is theoretical amount Basis 1 mole meth... View the full answer