thermometer thermometer heated area filter holder check valve temperature sensor stack wall probe silica gel reverse-type pitat tube pitot manometer thermometess inpingers Lice bath vacuum line taypass vatve Grit:ce majn valve dry gas meter airtight pump Figure 1.5

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30.19 Consider the device shown below that will be used to humidity an air stream. In the current process, air containing 1.0 mol% water vapor (species A) at 40°C and 1.0 atm enters the tube of 3.0 cm inner diameter at a velocity of 300 cm/s. A water- adsorbent material saturated with liquid water lines the inner surface of the tube. Water evaporates from this liner material as over it. There is no diffusion resistance of water vapor air passes Water adsorbent liner (1.0 mm thick, 0.6 g H,O/cm³ liner initially) Gas stream V =300 cm/sec D = 3.0 cm (tube) 1.0 atm, 40°C CA2 L = 8.0 m %3D through the liner material itself. The process is maintained at 40°C. The saturation vapor pressure of water is 55.4 mmHg at 40°C, At this temperature and 1.0 atm, the viscosity of air is 1.91 x 10¬4 g/cm · s and the density of air is 1.13x 10-3 g/cm³. a. What is the Schmidt number for this process? b. Develop a model, in final integrated form, to predict the concentration of water vapor exiting the tube.…

28.21 A 1 x 10-2 m spherical pellet is sprayed with a very thin coat of paint. The paint contains a volatile solvent. To dry the pellet, a 300 K and 1.013 × 105 Pa air stream flows around it with a bulk velocity of 1 m/s. The estimated loading of the solvent in the wet paint is 0.12 g solvent/cm³. Physical properties are vapor pressure of the solvent = 1.27 x 104 Pa mass diffusivity of solvent in air = 9.62 x 10-6 m²/s kinematic viscosity of air density of air = 1.569 x 10-5 m²/s = 1.177 kg/m³ thermal conductivity of air thermal diffusivity of air heat capacity of air = 2.624 x 10-2 J/m.s. K = 2.216 x 10-5 m²/s = 1.006 J/g. K = 78 g/g mole molecular weight of the solvent Use the McAdam's¹¹ equation Nu = 0.37(Redp) 0.6 (Pr) 1/3, where Redp dp vx V to evaluate (a) the heat-transfer coefficient, h; (b) the mass-transfer coefficient, ke; (c) the molar flux of the solvent into the air stream.

In a counter-current absorption tower, a process gas containing 0.04 (mole fraction) ammonia is scrubbed with pure water. The exit gas contains 0.002 (mole fraction) ammonia.The diameter of the tower is 1m, and the packing has a large area per volume of 200 m2m–3. The overall mass transfer coefficient based on the liquid side driving force, KL, is 1.5×10−5ms–1. The total gas and liquid concentrations are 0.6kmolm–3and 20 kmolm–3respectively and the gas flowrateis 0.03kmols–1. The actual liquid to gas ratio is 1.5 times that of the minimum liquid to gas ratio. The equilibrium for ammonia between the air and water is given by y* = 1.04x. What is the mol fraction of ammonia in the liquid?

8 i. Estimate the dimensions of a drying chamber for a spray dryer that has an output of 1000 kg/h of a heat-sensitive biological material at 60oC containing 5% moisture and having a mean particle size of 100 micrometers. The feed contains 40% solids by weight in an aqueous solution at 4oC. The inlet air has a humidity of 0.01 kg/kg dry air and is at 150oC, while the outlet air is at 80oC.

Forced air at T = 25°C and V = 10 m/s is used to cool electronic elements on a circuit board. One such ele- ment is a chip, 4 mm X 4 mm, located 120 mm from the leading edge of the board. Experiments have revealed that flow over the board is disturbed by the elements and that convection heat transfer is correlated by an expression of the form Nu,= 0.04 Re0.85 P.1/3 V. T uz bog fr dW ninin tol 1 = 4 mm Chip Board 0:00 Wira L= 120 mm Estimate the surface temperature of the chip if it is dis- sipating 30 mW.

I need help with questions e and f

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Question 7 of 10 Calculate the change in enthalpy of nitrogen when it is heated from 25 to 100 C. Select the correct response: 985.78 J/mol 2185.5 J/mol 3275.4 J/mol 1405.6 J/mol