How many meters of stairway (in height) could a 70 kg man climb if all the energy available in metabolizing an 11 g spoonful of sugar to carbon dioxide and water could be converted to work? For 1 mol of glucose oxidized to CO2 and H2O, 673 kcal of heat is released.
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find solutions to the following using Excel's matrix operations?
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A wastewater treatment plant has a rupture in one of their flow tubes, thereby leading to the discharge of waste material into a local lake system. The rupture goes unnoticed for a long enough time that the concentration of the waste in the lake reaches a steady state. Assume that the lake can be modeled as a continuously stirred tank reactor, with inflow, outflow, and complete mixing, and that the lake flows so that the volume remains constant at 107 m3. Pollutant-free water enters the lake at a volumetric flowrate of 45 m3/s. The waste from the wastewater treatment plant (that flows into the lake) has a waste concentration of 120 mg/L and a volumetric flowrate of 6 m3/s. Thus, there are two inlets to the lake, one with unpolluted water and the other with polluted water. The waste naturally decays according to the rate relationship, k*Cwaste , where k = 0.15 day-1. Determine the steady state concentration of waste in the lake, in units of mg/L (milligrams per liter). Express your answer to one decimal place.
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You are working in a company that has developed a process to produce DNA vaccines from E. coli. After the fermentation step a lysis step is used to release the DNA from the cells resulting in a viscous mixture. You find that an aggressive cleaning solution heated to 80°C is required to clean the sticky mixture off the inside of the lysis tank. A countercurrent shell-and-tube heat exchanger containing 100 tubes is used to heat the cleaning solution from 10 C to 80°C at a mass flow rate of 8.6 kgs-1. The tubes have external and internal diameters of 11 mm and 10 mm, respectively, and a thermal conductivity of 17 W m-I K-I . Water enters the shell at 90°C at a mass flow rate of 22 kgs-1. The shell side heat transfer coefficient is 2500 W m2 K-1
You are given the following data: The following correlation appliesfor turbulentflow in pipes: Nu = 0.023 Re^o.8 Pr^0.4 . Cleaning Solution: Thermal conductivity = 0.5 Wm-1 K-1 Viscosity = 1 x 10-3 Pa s Specific heat capacity = 3.68 kJ kg-l K 1 Density = 1,100 kg m3 Water Specific heat capacity = 4.18 kJ kg-l KCalculate the surface area available inside the heat exchanger.
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The purchased cost of a shell-and-tube heat exchanger (floating-head and carbon-steel tubes) with 100 m2 of heating surface was $4500 in 1990. What will be the 1990 purchased cost of a similar heat exchanger with 20 m2 of heating surface if the purchased cost capacity expo- nent is 0.60 for surface areas ranging from 10 to 40 m2? If the purchased cost capacity expo- nent for this type of exchanger is 0.81 for surface areas ranging from 40 to 200 m2, what will be the purchased cost of a heat exchanger with 100 m2 of heating surface in 2000?
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An aqueous alkaline solution is 20 wt% NaOH and has a specific gravity of 1.222. It flows through a 5 inch diameter pipe at a rate of 20 gpm (gallons per minute).
A) What is the mean velocity of the solution in the pipe?
B) What is the mole fraction NaOH in the solution?
C) What is the molarity of NaOH in the solution?
D) The solution is for use in an oil refinery, where they like to use “barrels per day” for units of flow rate. What is the flow rate of the solution in barrels per day?
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An insulated tank, fitted with a freely moving frictionless piston, has an initial volume of 1 m3 and contains 20 kg of refrigerant 134a at 200 kPa. A stirrer with a rotation rate of 300 rpm and a torque of 15 J/rotation is included in the tank. Find the time required for the refrigerant to evaporate completely.
Ans= [73.36 minutes]
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Quickly estimate the change in enthalpy (J/mol) to go from CO2 at 223K and 10 bar to 298K and 90 bar and sketch a graph.
Quickly estimate the change in internal energy (J/mol) to go from CO2 at 273K and 10 bar to 340K and 105 bar.
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Consider a hypothetical metal that has a density of 8.40 g/cm3, an atomic weight of 108.6 g/mol, and an atomic radius of 0.136 nm. Compute the atomic packing factor if the unit cell has tetragonal symmetry; values for the A and C lattice parameters are 0.494 and 0.352, respectively.
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For a distillation coloumn sperperating a non-ideal liquid mixture using ASPEN PLUS, which thermodynamic model should I use (NRTL, UNIQUAC, UNIFAC, etc) and why should I use this specific model and not the others (justification required)
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Mercury has a surface tension coefficient σ = 0.487N/m. A Mercury barometer has a cylindrical tube that is 5mm in diameter.
a) By how many mm will the Mercury level change due to capillary forces? Follow the procedures and assumptions of the example in the notes.
b) Air pressure at sea level typically causes Mercury level to rise by 760mm. What is the percent error due to capillary force?
c) Repeat parts a and b for a tube that is 0.1mm in diameter.
d) Repeat parts a and b for a tube that is 20mm in diameter.
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Oxidative dehydrogenation of ethane is the conversion of ethane with oxygen to yield ethylene and water.In addition to oxidative dehydrogenation, ethane/oxygen mixtures can also undergo partial oxidation, i.e. the formation of synthesis gas (CO and H2), as well as total oxidation, i.e. complete combustion of ethane towards CO2 and water.Hydrogen is of great interest as a feed for fuel cells. However, in order to use the hydrogen content of the syngas produced via partial oxidation of ethane, one would need to remove virtually all the CO from the mixture since CO is a strong poison for most fuel cells. This could be done through addition of steam in order to convert the CO via the so-called ‘water gas shift’ reaction (WGS: CO + H2O = CO2 + H2). Assuming a feed flow of 100 L/min of a feed mixture 75vol% air and 25vol% ethane, and furthermore assuming that the partial oxidation reaction goes to completion, how much steam needs to be added in order to completely convert the CO? (Assume stoichiometric conversion via WGS.) What is the composition of the effluent stream (in molar fractions)?
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A gas is leaking from a rigid tank into the air. Which of the following represents the BEST energy balance?
| a |
d(nU) = Hdn |
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| b |
Δ(nU) = HΔn |
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| c |
ΔU = Q + W |
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| d |
ΔH = Q + W Which of the following is the first step to solving a thermodynamics problem?
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Determine, using the procedures outlined by RCRA, if each of the following is a hazardous waste. State the reason why it is or is not a hazardous waste. If it is a hazardous waste, list the RCRA waste category number. Assume that the industry producing the waste is a RCRA hazardous waste generator.
a.Soil on the industrial property contaminated by the spill of a 5-gallon (18.9 L) container of endrin.
b.A drum of off-specification ethyl acetate that is to be disposed of.
c.Cement kiln waste.
d.Sawdust in a warehouse contaminated by a spill of pentachlorobenzene.
e.Distillation bottoms from aniline production.
f.Sludge from the treatment of water from the chemical conversion coating of aluminum.
g.1000 Kg of commercial beryllium (pure) that are to be discarded because the company that purchased this chemical originally doesn’t need it anymore.
h.An aqueous industrial waste stream from a plastic manufacturing plant that is discharged to a river.
i.A drum of sulfuric acid at pH 0.50.
j.A drum of waste 20% perchloroethylene.
k.Spent cyanide plating bath solutions from electroplating operations. .
l.Wastewater treatment sludge from the production of zinc yellow pigments. .
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