1. A mixture of gases containing 14 kg of nitrogen (N2), 20 kg of hydrogen (H2), and 12 kg of helium (He) is contained at a pressure of 1.2 MPa and a temperature of 293 K. If the constituents are taken to be perfect gases and Dalton's law of partial pressures holds, what are the molecular weight and specific heat ratio of the mixture? Gas Mole wt, M (g/mol) Specific heat ratio, y Nitrogen 28 1.4 Hydrogen 2 1.4 Helium 4 1.67

Psychrometric process A room has dimensions of approximately 10m x 10m x 3m. Assume the air inside the room to be at T= 20 oC, P = 100 kPa, Relative Humidity = 50% a. If all of the water vapor in the air of the room could be converted to liquid at the same temperature, what is the volume of the liquid (mL)? b. If the room temperature were slowly cooled without changing the composition of air, at what temperature would you expect to see condensation occurring (oC)?

Q: The specific gravity of a solution of KOH at 15°C is 1.0824 and contains 0.813 Ib KOH per U.S. gal of solution. (A) What are the mass fractions of KOH and H2O in the solution? (B) What is the volume in (m3) of 325 kilograms of this solution at the same temperature (15°C)? Q: In a gas-separation plant, the feed to the process has the following constituents: component Mole % Cudeer overhead C3 1.9 Reflus Feed DC i- C4 51.5 n-C4 46 Bottom C5 0.6 Total 100

RP-1 is highly refined form of kerosene used for many first stage rocket engines. The average composition of it is indicated by CH1.9 a. What is the stoichiometric mixture ratio (MR) for RP-1 and oxygen? b. Now, you have a mixture of air and RP-1 with three times more air (in terms of moles) than is needed to burn all the fuel. How high is the final temperature? The heats of formation are given in the table below. In molar quantities, assume 1 mole of air is (O2+3.76N2). The reactants have a temperature of 25°C before combustion. You may use the average values of the specific heats for each constituent. C. Would the adiabatic flame temperature be lower or higher for a rocket engine that uses pure oxygen instead of air? Explain. Constituent Qf kJ/kmol @ 298 K Cp kJ/kmol K CH19 9,358 CO2 (g) -393,522 51.9 O2 (g) 0 34.0 N2 (g) 0 31.6 H₂0 (g) -241.827 40.6

A vessel contains at 1 bar and 20°C a mixture of 1 mole of CO2 and 4 moles of air. Calculate for the mixture: (i) The masses of CO2, Oz and N2; (ii) The percentage carbon content by mass; (iii) The apparent molecular weight and the gas constant for the mixture; (iv) The specific volume of the mixture; (v) If the mixture is heated at constant pressure to 100°C, find the changes in internal energy, enthalpy and entropy of the mixture.

An air-water vapor mixture has a relative humidity of 40% and an enthalpy of 50 kJ/kg. What is the temperature (i.e., dry bulb temperature), wet bulb temperature, and humidity of the mixture? (Use the psychrometric chart, Figure 23.14)

A vessel contains at 1 bar and 20°C a mixture of 1 mole of CO2 and 4 moles of air. Calculate for the mixture: (i) The masses of CO2, O2 and N2; (ii) The percentage carbon content by mass; (iii) The apparent molecular weight and the gas constant for the mixture; (iv) The specific volume of the mixture; (v) If the mixture is heated at constant pressure to 100°C, find the changes in internal energy, enthalpy and entropy of the mixture.

0.5 kg of Helium and 0.5 kg of nitrogen are mixed at 20 degrees * C and at a total pressure of 100 kPa. Find (a) the volume of the mixture (b) the partial volumes of the components (c) the partial pressures of the components (d) the mole fraction of the components (e) the specific heats c_{p} and c, of the mixture and (f) the gas constant of the mixture.

3. Assuming that air may be treated as a mixture of ideal gases which has a mass composition 23.2% oxygen and 76.8% nitrogen, find the gas constant and apparent molecular weight of air. [Ans. 0.288 kJ/kg K, 28.86]

0.5 kg of Helium and 0.5 kg of nitrogen are mixed at 20 degrees * C and at a total pressure of 100 kPa. Find (a) the volume of the mixture (b) the partial volumes of the components (c) the partial pressures of the components (d) the mole fraction of the components (e) the specific heats c_{p} and c, of the mixture and (f) the gas constant of the mixture.