Questions and Answers of Chemical Biochemical And Engineering

Derive the equations that replace Eqs. 15.1-3 and 15.3-4b if electrolyte solution nonideality is included. ST (pH) = So+ S.. KHA MH+ (15.1-3)
Redo Illustration 7.5-3 with the Soave–RedlichKwong equation of state. Compare the results obtained with those for the Peng-Robinson equation in the illustration. Also, repeat the calculations for
A heat exchanger is a device in which heat flows between two fluid streams brought into thermal contact through a barrier, such as a pipe wall. Heat exchangers can be operated in either the cocurrent
The compressor discussed in Illustrations 3.4-4 and 4.5-1 is being used to compress air from 1 bar and 290 K to 10 bar. The compression can be assumed to be adiabatic, and the compressed air is found
The piston-and-cylinder device of Illustration 3.4-7 is to be operated in reverse to isothermally compress the 1 mol of air. Assume that the weights in the illustration have been left at the heights
Consider the following statement: “The adiabatic work necessary to cause a given change of state in a closed system is independent of the path by which that change occurs.”a. Is this statement
a. One kilogram of steam contained in a horizontal frictionless piston and cylinder is heated at a constant pressure of 1.013 bar from 125°C to such a temperature that its volume doubles. Calculate
Water in an open metal drum is to be heated from room temperature (25°C) to 80°C by adding steam slowly enough that all the steam condenses. The drum initially contains 100 kg of water, and steam
As an energy conservation measure in a chemical plant, a 40-m3 tank will be used for temporary storage of exhaust process steam. This steam is then used in a later stage of the processing. The
The mixing tank shown here initially contains 50 kg of water at 25°C. Suddenly the two inlet valves and the single outlet valve are opened, so that two water streams, each with a flow rate of 5
A well-insulated storage tank of 60 m3 contains 200 L of liquid water at 75°C. The rest of the tank contains steam in equilibrium with the water. Spent process steam at 2 bar and 90 percent quality
a. An adiabatic turbine expands steam from 500°C and 3.5 MPa to 200°C and 0.3 MPa. If the turbine generates 750 kW, what is the flow rate of steam through the turbine? b. If a breakdown of the
Intermolecular forces play an important role in determining the thermodynamic properties of fluids. To see this, consider the vaporization (boiling) of a liquid such as water in the frictionless
Nitrogen gas leaves a compressor at 2.0 MPa and 120°C and is collected in three different cylinders, each of volume 0.3 m3. In each case the cylinder is to be filled to a pressure of 2.0 MPa.
In Illustration 3.4-6 we considered the compression of an ideal gas in which P V⋎ = constant, where ⋎ = C∗P/C∗V. Show that such a pressure-volume relationship is obtained in the adiabatic
Redo Problem 3.5 using Aspen Plus.Problem 3.5Steam at 500 bar and 600°C is to undergo a JouleThomson expansion to atmospheric pressure. What will be the temperature of the steam after the expansion?
Redo Problem 3.16a using Aspen Plus.Problem 3.16aAn adiabatic turbine expands steam from 500°C and 3.5 MPa to 200°C and 0.3 MPa. If the turbine generates 750 kW, what is the flow rate of steam
a. A steam turbine in a small electric power plant is designed to accept 4500 kg/hr of steam at 60 bar and 500°C and exhaust the steam at 10 bar. Assuming that the turbine is adiabatic and has been
Two tanks are connected as shown here. Tank 1 initially contains an ideal gas at 10 bar and 20°C, and both parts of tank 2 contain the same gas at 1 bar and 20°C. The valve connecting the two tanks
An inventor has proposed a flow device of secret design for increasing the superheat of steam. He claims that a feed steam at 1 bar and 100°C is converted to superheated steam at 1 bar and 250°C
Consider the Hilsch-Ranque vortex tube discussed in Illustration 4.5-6. Starting with air at 4 bar and 25°C, an exhaust pressure of 1.013 bar, and that half the air that enters the tube will be
Consider the Hilsch-Ranque vortex tube discussed in Illustration 4.5-6. Starting with air at 4 bar and 25◦C, and exhaust pressure of 1.013 bar, and that half the air that enters the tube will be
A coal-fired power plant had been operating using a standard Rankine cycle to produce power. The operating conditions are as given in Illustration 5.2-1. However, the boiler is aging and will need to
Use Aspen Plus to compute the coefficient of performance of a Rankine cycle using water as the working fluid (described by the IAPWS-95 method) and the following state conditions: Condenser:
Calculate the molar volume, enthalpy, and entropy of carbon tetrachloride at 300°C and 35 bar using the Peng-Robinson equation of state and the principle of corresponding states of Sec. 6.6. The
The force required to maintain a polymeric fiber at a length L when its unstretched length is L0 has been observed to be related to its temperature bywhere γ is a positive constant. The heat
Redo Problem 6.65 using Aspen PlusProblem 6.65Pipelines are used to transport natural gas over thousands of miles, with compressors (pumping stations) at regular intervals along the pipeline to
Liquid ethanol, for which κT = 1.09 × 10−6 kPa−1, has a relatively high isothermal compressibility, which can have a significant effect on its fugacity at high pressures. Using the data in the
Using the information in Problems 7.13 and 8.20, estimate the heat of vaporization for the first bit of ethanol from ethanol-water solutions containing 25, 50, and 75 mol % ethanol and from a
Steele et al. [ J. Phys. Chem. Soc., 96, 4731 (1992)] used bomb calorimetry to compute the standard enthalpy of combustion of solid buckminsterfullerene (C60) at 298.15 K to be 26 033 kJ/mol.
Develop a Gibbs-Duhem equation for strong electrolyte-water systems, and use this equation and the data in Illustration 9.10-1 to compute the activity coefficient of water in aqueous hydrochloric
Repeat the derivations of the previous problem for a mixing process in which both pure fluids, initially at a temperature T and pressure P, are mixed at constant temperature and the pressure then
Repeat the calculations of the previous problem with the regular solution model. Compare the two results.previous problem Chemically similar compounds (e.g., ethanol and water or benzene and
Repeat the calculation of the previous problem using Aspen Plus and the Peng-Robinson equation with its default parameters.previous problemA natural gas stream 90 mol % CH4 (component 1) contaminated
Redo Problem 9.22 using Aspen Plus.Problem 9.22a. Given experimental data either for the excess Gibbs energy, Gex, or for species activity coefficients from which Gex can be computed, it is sometimes
The dissociation pressure of calcium oxalate in the reaction at various temperatures isCompute the standard-state Gibbs energy change, enthalpy change, and entropy change for this reaction for the
The following data are available for the solubility of barium sulfate in water: where values for the parameter α for water are given in Table 9.10-1.a. Compute K°s , the ideal solution solubility
The Soviet Venera VII probe, which reached Venus on December 15, 1970, found the following conditions on the planet surface: Interferometric measurements indicate that there is only a 10 to 20 K
At 452.2 K, a total pressure of 95.9 kPa, and with an appropriate catalyst, the equilibrium extent of dissociation of pure isopropanol to acetone and hydrogen is found to be 56.4 percent [H. J. Kolb
Repeat the calculations of Illustrations 13.4-1 and 13.4-2 for 50°C. The Henry’s law constant for ammonia in water at this temperature is HHN3 = 384.5 kPa/mole fraction, and you can assume that
The industrial solvent carbon disulfide can be made from the reaction between methane and hydrogen sulfide at elevated temperatures using the following reaction gas-phase reaction: a. Compute the
Formaldehyde CH2O can be produced by the gasphase pyrolysis of methanol CH3OH by the following reactionAssuming the ΔrxnH is independent of temperature, a. Compute the equilibrium extent of
Redo Problem 14.3 with the change that the reactor is to operate at a constant pressure of 1.0 bar (instead of at constant volume) and that the initial pressure is 1.0 bar.Problem 14.3 One mole of
An equimolar mixture of isopropylene and benzene react at 275°C and 10 bar to form isopropylbenzene. Determine the equilibrium phases present and their composition at these conditions.
Equal amounts of pure nitrogen and pure oxygen, each at 3000 K and 1 bar, are continuously fed into a chemical reactor, and the reactor effluent, consisting of the reaction product nitric oxide and
An unsecured tank contains 20 kg of n-butane at its vapor pressure at 25°C. The cylinder falls over, breaking off the valve and releasing the entire contents of the cylinder, and the resulting vapor
Derive Eq. 14.3-17.Eq. 14.3-17. W max = Σ(N;A;)inal - Σ(N;A;)initial i=1 i=1 (14.3-17)
Redo Problem 14.1 using Aspen Plus.Problem 14.1The flame temperature attained in a torch or a burner can be computed using the adiabatic reaction temperature analysis of Sec. 14.3 if it is assumed
Reading from the graphs in the paper by M. M. Santoro and D. W. Bolen, Biochem. 31, 4901-4907 (1992) the following data are obtained for the Gibbs energy change on chemical denaturation
Repeat the calculation of the previous problem if 100% excess air is used.previous problemOctane can be used as a model for gasoline. If octane is available at ambient conditions and used in an
M. M. Santoro and D. W. Bolen, Biochem. 31, 4901- 4907 (1992) report the following data for the thermal denaturation (folded-unfolded transition) of E. coli Thioredoxin as a function of NaCl
When a yeast of average biomass composition is grown on an aqueous solution of methanol with dissolved nitrogen, it is found that 400 g of dry yeast are produced for each kilogram of methanol
The following data have been reported by von Stockar and Birou for biomass production and heat release for the fermentation of glucose by K. fragilis, which also produces ethanol as the
When the bacterium Zymomonas mobilis is used to produce ethanol from glucose in an anaerobic process with ammonia as the nitrogen source, it is found that bacteria biomass is produced to the extent
Repeat Illustration 15.7-10 if nitric acid C5H9NO4 is used as the nitrogen source instead of ammonia.Illustration 15.7-10Choosing a Substrate for a Fermentation An unspecified substrate that does
Derive the analogue of Eqs. 15.7-6 for Gibbs-Donnan equilibrium involving a negatively charged protein. YQ/s = (Ńs)1 - (Ńs)3 (15.7-6)
Glucose and fructose both have the composition C6H12O6, but differ slightly in structure, as shown below, and more so in sweetness. Repeat Illustration 15.7-9 using these sugars instead of xylose.a.
Succinic acid, which has the structure HOOC—CH2—CH2—COOH and on a C-mole basis is represented by CH3/2O, is useful as a starting material in the manufacture of solvents and polymers. It is
The biologist of Illustration 15.7-9 is examining other genetically engineered bacteria to produce 2,3- butanediol from lignins, which are derived from abundant and renewable resources such as trees,
A considerable amount of methane is produced in Norway from its North Sea oil and gas wells. Some of this methane is converted to methanol by partial oxidation, and then biochemically converted to
Another possibility is to convert the methane directly to biomass that is used as animal feed. The stoichiometry for this biochemical reaction is It has been found that the consumption of 2.5 m3 of
The compound 1,3-propanediol, which has the structure HO—CH2—CH2—CH2—OH, is a monomer used in the production of polyester fibers and in the manufacture of polyurethanes. 1,3 Propanediol can
Various different substrates are being considered for the biochemical production of 1,3-propanediol (see previous problem) using dissolved ammonia as the nitrogen source. Determine the maximum amount
The bacterium Zymomonas mobilis can reproduce while producing ethanol from glucose in an anaerobic (i.e., without added oxygen) continuous process using ammonia as the nitrogen source. It has been
It has been claimed that coal, which we can consider to be pure carbon, can as a result of microbial action react with water in situ and be converted to methane by the reaction: Is this reaction
A proposed chemical composition for anthracite coal is C240H90O4NS. The stoichiometry for a biochemical reaction of anthracite with water is as follows:Determine the maximum thermodynamically allowed
Biogas is produced as in an anaerobic digester that treats farm wastes or energy crops. During the process, an air-tight tank transforms biomass waste into methane, producing renewable energy that
A centrifuge operating at 5000 rpm and 25°C is to being used to partially separate antipneumococcus serum globulin (molecular weight 195 000 and partial molar volume of 0.745 cc/g) from hemoglobin
An ultracentrifuge is found to have a lysozyme concentration of 1 mg/g of water 2 cm from the axis of rotation. Determine the equilibrium concentration profile over the range from 2 cm to 4 cm from
Repeat Illustration 14.5-1 if 50% excess air is used.Illustration 14.5-1Determine the maximum useful shaft work that can be obtained from natural gas that we will model as methane, which is available
If octane is burned in a closed, constant volume reactor with 20% excess air, what is the maximum amount of shaft work that can be produced?
If octane is burned in a closed, constant volume reactor with a stoichiometric amount of oxygen, what is the maximum amount of shaft work that can be obtained?
Octane can be used as a model for gasoline. If octane is available at ambient conditions and used in an automobile engine, which can be considered to be a continuous flow reactor, what is the maximum
Methanol and acetic acid can react in the liquid phase to form methyl acetate and water. Determine the equilibruim compositions of this mixture at 150°C and 50 bar using the NRTL model and either
Redo Problem 14.13 using Aspen Plus.Problem 14.13Equal amounts of pure nitrogen and pure oxygen, each at 3000 K and 1 bar, are continuously fed into a chemical reactor, and the reactor effluent,
Redo Problem 14.2 using Aspen Plus.Problem 14.2Compute the flame temperature of an oxyacetylene torch using pure acetylene and 50 percent more pure oxygen than is needed to convert all the acetylene
Redo Problem 14.3 using Aspen Plus.Problem 14.3One mole of ethylene and one mole of benzene are fed to a constant-volume batch reactor and heated to 600 K. On the addition of a catalyst, an
Redo Problem 14.12 using Aspen Plus.Problem 14.12Redo Problem 14.3 with the change that the reactor is to operate at a constant pressure of 1.0 bar (instead of at constant volume) and that the
Redo Problem 14.8 using Aspen Plus.Problem 14.8Methane is to be burned in air. Determine the adiabatic flame temperature as a function of the methane-to-air ratio at a pressure of 1 bar.
a. What is the solubility product for silver sulfate, Ag2SO4, in water?b. An electrolytic silver-producing cell consists of a copper cathode, a silver anode, and a solution that initially contains
Compare your answer above with the maximum amount of work that could be obtained from methane if a nonthermal energy conversion route, such as a fuel cell, was used.
Estimate the maximum amount of work that can be obtained from the controlled combustion of methane in air at 1 bar as a function of the methane-to-air ratio. Assume that the process is as follows.
Methane is to be burned in air. Determine the adiabatic flame temperature as a function of the methane-to-air ratio at a pressure of 1 bar.
Estimate the maximum amount of work that can be obtained from the combustion of gasoline, which we will take to be represented by n-octane (C8H18), in an automobile engine. For this calculation,
There are two beakers, each one liter in total volume. One of the beakers contains copper sulfate at a concentration of 0.0001 M and the other contains a 0.01-M solution of the same salt. Compute the
One of the purposes of the kidneys is to transfer useful chemicals from the urine to the blood, and toxins from the blood to the urine. In the transport of glucose from the urine to the blood, the
How would you determine the entropy change and the enthalpy change of an electrochemical cell reaction?
One mole of ethylene and one mole of benzene are fed to a constant-volume batch reactor and heated to 600 K. On the addition of a catalyst, an equilibrium mixture of ethylbenzene, benzene, and
Compute the flame temperature of an oxyacetylene torch using pure acetylene and 50 percent more pure oxygen than is needed to convert all the acetylene to carbon dioxide and water. Both the oxygen
The flame temperature attained in a torch or a burner can be computed using the adiabatic reaction temperature analysis of Sec. 14.3 if it is assumed that the radiant heat loss from the flame is
Redo Problem 13.48 using Aspen Plus.Problem 13.48The chemical reaction for the dissociation of nitrogen tetroxide is N2O4(g) → 2NO2(g)The reported standard-state Gibbs energy change for this
Redo Problem 13.47 using Aspen Plus.Problem 13.47The reactionis used as a step in the process to convert waste sulfur dioxide to sulfuric acid. Starting with stoichiometric amounts of sulfur dioxide
Redo Problem 13.46 using Aspen Plus.Problem 13.46While ethanol can be made by biological fermentation, for large-scale production the following nonbiological reaction starting with ethylene and water
Redo Problem 13.44 using Aspen Plus.Problem 13.44At high temperatures—for example, in a combustion process—nitrogen and oxygen in air can react to form nitrous oxide, Starting with air (79 mol %
Redo Problem 13.37 using Aspen Plus.Problem 13.37At an appropriate temperature, a larger alkane will “crack” to form a smaller alkane and an olefin. One example is the cracking of propane to form
Redo Problem 13.36 using Aspen Plus.Problem 13.36The industrial solvent carbon disulfide can be made from the reaction between methane and hydrogen sulfide at elevated temperatures using the
Redo Problem 13.32 using Aspen Plus. Problem 13.32Liquid benzene can be catalytically hydrogenated, with cyclohexene, cyclohexane, and 1,3-cyclohexadiene being among the products. Determine the
Redo Problem 13.31 using Aspen Plus.Problem 13.31At 452.2 K, a total pressure of 95.9 kPa, and with an appropriate catalyst, the equilibrium extent of dissociation of pure isopropanol to acetone and
Redo Problem 13.30 using Aspen Plus.Problem 13.30The liquid in a two-phase, binary mixture of benzene and cyclohexane has a composition of 20 mol % of benzene and 80 mol % of cyclohexane at T =
Redo Problem 13.28 using Aspen Plus.Problem 13.28A gas mixture containing equimolar quantities of carbon dioxide and hydrogen is to be “reformed” by passing it over a catalyst. The pressure in

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