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An air conditioner in the airport of Timbuktu runs a cooling system using R-410a with a high pressure of 1800 kPa and a low pressure of 200 kPa. It should cool the desert air at 45C down to 15C. Find... A steam power plant has a high pressure of 3 MPa, and it maintains 60C in the condenser. A condensing turbine is used, but the quality should not be lower than 90% at any state in the turbine. For a... A stirred tank with volume V t (L) is charged with V l (L) of a liquid, B. The space above the liquid (volume V g = V t - V l ) is filled with a pure gas, A, at an initial pressure P 0 (atm). The... In hydrophilic interaction chromatography (HILIC), why is eluent strength increased by increasing the fraction of water in the mobile phase? Fuel cells have been proposed as an alternative energy technology for use in stationary and transportation applications. A fuel cell is an electrochemical device in which hydrogen reacts with oxygen... Suppose that 0.010 0 M Mn 2+ is titrated with 0.005 00 M EDTA at pH 7.00. (a) What is the concentration of free Mn 2+ at the equivalence point? (b) What is the quotient [H 3 Y - ]/[H 2 Y 2- ] in the... Why do open tubular columns provide greater resolution than packed columns in gas chromatography? What is the absolute uncertainty in mass (? Da) at m/z 100 and at m/z 20 000 if the mass accuracy of a spectrometer is 2 ppm? Metallic iron is produced in the reaction between ferrous oxide and carbon monoxide: The flowchart shown below depicts this process for a basis of 1 mol FeO fed at 298 K. (a) We wish to explore the... A tracer is used to characterize the degree of mixing in a continuous stirred tank. Water enters and leaves the mixer at a rate of V (m 3 /min). Scale has built up on the inside walls of the tank, so... In respiration, air is inhaled into the lungs, which provide a large surface area for transport of oxygen, carbon dioxide, and water to or from the blood. The transported oxygen is delivered to body... a. Which of the following compounds will form hydrogen bonds between its molecules? 1. CH 3 CH 2 CH 2 COOH 2. CH 2 CH 2 N(CH 3 ) 2 3. CH 3 CH 2 CH 2 CH 2 Br 4. CH 3 CH 2 CH 2 NHCH 3 5. CH 3 CH 2 OCH... Find the heat of evaporation, hfg, for R-134a at 30 F from the generalized charts and compare to the value in Table F. 10. Consider a binomial experiment with n = 20 and p = .70. a. Compute f (12). b. Compute f (16). c. Compute P(x 16). d. Compute P(x 15). e. Compute E(x). f. Compute Var (x) and s. Cumene (C 6 H 5 C 3 H 7 ) is produced by reacting benzene with propylene [H r (77F) = -39;520 Btu]. A liquid feed containing 75 mole% propylene and 25% n-butane and a second liquid stream containing... Which structure does not represent 2-methylpentane? a. b. c. d. Assign (R ) or (S ) designations to each of the following compounds: a. b. c. d. H,C, CI Solid oxide fuel cells (SOFC) have been proposed as an alternative energy technology for use in large stationary power applications (1 to 10MWof electrical power). These devices have an ion... A city with a population of 200,000 people operates a 20:0 10 6 gal/day wastewater treatment plant. For every million gallons of wastewater treated, 1875 lbm of solids are generated, with 75% of the... Natural gas that contains methane, ethane, and propane is to be burned with humid air. The adiabatic flame temperature is to be calculated from specified values of the following quantities: (a)... Explain the meaning of each of the following terms. In your answer include an example to help with your explanation. a. Expansion. b. Contraction. c. Physical change. d. Sublimation. e. Diffusion. f.... Acetylene is produced by pyrolyzingdecomposing at high temperaturenatural gas (predominantly methane): The heat required to sustain this endothermic reaction is provided by feeding oxygen to the... The wastewater treatment plant at the Ossabaw Paper Company paper mill generates about 24 tonnes of sludge per day. The consistency of the sludge is 35%, meaning that the sludge contains 35 wt%... This question is about FORCE and ACCELERATION. The driver of a car moving at 20 m/s along a straight level road applies the brakes. The car decelerates at a steady rate of 5 m/s 2 . a. How long does... The flow rate of a process stream has tended to fluctuate considerably, creating problems in the process unit to which the stream is flowing. A horizontal surge drum has been inserted in the line to... a. Write down, in words, the equation connecting speed, distance and time. b. A car travels at a steady speed of 20 m/s. Calculate the distance travelled in 5 s. An unstable nucleus has 137 neutrons and 88 protons. It decays by emitting a -particle. How many neutrons and protons does the nucleus have after emitting the -particle? neutrons protons A 136 88 B... Purification of proteins for use as biopharmaceuticals is often accomplished by ion exchange chromatography, in which a process fluid passes through a column packed with small resin beads whose ionic... Birch reduction of toluene leads to a product with the molecular formula C 7 H 10 . On ozonolysis followed by reduction with dimethyl sulfide, the product is transformed into What is the structure of... Methane is generated via the anaerobic decomposition (biological degradation in the absence of oxygen) of solid waste in landfills. Collecting the methane for use as a fuel rather than allowing it to... The demand for biopharmaceutical products in the form of complex proteins is growing. These proteins are most often produced by cells genetically engineered to produce the protein of interest, known... Iram has 12 different DVDs of which 7 are films, 3 are music videos and 2 are documentaries. a. How many different arrangements of all 12 DVDs on a shelf are possible if the music videos are all next... Boron is an element in Group 13 of the Periodic Table. a. Boron has two isotopes. What do you understand by the term isotope? b. State the number of i protons, ii neutrons and iii electrons in one... Phosgene (COCl 2 ) is formed by CO and Cl 2 reacting in the presence of activated charcoal: At T = 303:8 K the rate of formation of phosgene in the presence of 1 gram of charcoal is where C denotes... A gas that contains CO 2 is contacted with liquid water in an agitated batch absorber. The equilibrium solubility of CO 2 in water is given by Henrys law (Section 6.4b) C A = p A /H A where C A... Predict the products and propose mechanisms for the following reactions. a. b. c. d. H+ OCH,CH3 excess H,0 Draw dot-and-cross diagrams for the ions in the following ionic compounds. Show only the outer electron shells. a. Potassium chloride, KCl b. Sodium oxide, Na 2 O c. Calcium oxide, CaO d. Magnesium... Many of the condensations we have studied are reversible. The reverse reactions are often given the prefix retro-, the Latin word meaning backward. Propose mechanisms to account for the following... By referring to the periodic table (Figure 2.15 or inside front cover), identify the group and period to which each of the following elements belongs. Then decide whether the element is a metal,... a. i. On analysis a hydrocarbon was found to contain 0.72 g of carbon and 0.18 g of hydrogen. What is the empirical formula of the hydrocarbon? ii. Further investigation showed that the relative... A stone is dropped into a fast-flowing stream. It does not fall vertically because of the sideways push of the water (Figure 4.7). a. Calculate the resultant force on the stone. b. Is the stone in... Multiple-Concept Example 7 deals with the concepts that are important in this problem. A penny is placed at the outer edge of a disk (radius = 0.150 m) that rotates about an axis perpendicular to the... Multiple-Concept Example 7 reviews the concepts that play a role in this problem. Car A uses tires for which the coefficient of static friction is 1.1 on a particular unbanked curve. The maximum... Review Conceptual Example 7 in preparation for this problem. In tests on earth a lunar surface exploration vehicle (mass = 5.90 10 3 kg) achieves a forward acceleration of 0.220 m/s 2 . To achieve... On your flight out of South America your cargo plane emergency-lands on a deserted island somewhere in the South Pacific. Because it was a beach landing, the pilot skids the plane on its belly rather... Multiple-Concept Example 9 reviews the concepts that play a role in this problem. Two forces are applied to a tree stump to pull it out of the ground. Force F A(vector) has a magnitude of 2240... Multiple-Concept Example 9 deals with the concepts that are important in this problem. A grasshopper makes four jumps. The displacement vectors are (1) 27.0 cm, due west; (2) 23.0 cm, 35.0 south of... Calculate the force needed to give a car of mass 800 kg an acceleration of 2.0 m s 2 . You are running from pirates on a tropical island somewhere in the Caribbean. You have somehow become separated from the rest of your group and now find yourself on the edge of a cliff with your... Rumor has it that a company has been smuggling gold out of the country using sealed, cylindrical barrels with hollow walls. They pour molten gold into the hollows, and then fill the remainder of the... Review Conceptual Example 7 as background material for this problem. A jet transport has a weight of 1.00 106 N and is at rest on the runway. The two rear wheels are 15.0 m behind the front wheel,... The Earth takes one year to orbit the Sun at a distance of 1.5 10 11 m. Calculate its speed. Explain why this is its average speed and not its velocity. You are in a sledding contest where you start at a height of 40.0 m above the bottom of a valley and slide down a hill that makes an angle of 25.0 with respect to the horizontal. When you reach the... You and your exploration team are stuck on a steep slope in the Andes Mountains in Argentina. A deadly winter storm is approaching and you must get down the mountain before the storm hits. Your path... A snail crawls 12 cm in one minute. What is its average speed in mm s 1 ? A car travels one complete lap around a circular track at a constant speed of 120 km h 1 . a. If one lap takes 2.0 minutes, show that the length of the track is 4.0 km. b. Explain why values for the... Review Conceptual Example 14 before attempting this problem. The truck in that example is traveling at 27 m/s. The density of air is 1.29 kg/m 3 . By how much does the pressure inside the cargo area... You and your team are given the task of constructing a crude thermometer that covers a temperature range from 0 C to 60 C. You have at your disposal an aluminum rod of length L 0 = 2.00 m (at T = 0... Conceptual Example 5 provides background for this problem. A hole is drilled through a copper plate whose temperature is 11 C. (a) When the temperature of the plate is increased, will the radius of... An object falls at terminal velocity in air. What overall conversion of energy is occurring? A. Gravitational potential energy to kinetic energy B. Gravitational potential energy to thermal energy C.... You and your team are asked to determine the hearing safety parameters for a loud experiment. Since the sound will persist for only a short time, the allowed intensity level that will not result in... Two balls, each of mass 0.50 kg, collide as shown in Figure 6.6. Show that their total momentum before the collision is equal to their total momentum after the collision. before after 2.0 m s-1 3.0... An object has mass 2.0 0.2 kg and a velocity of 10 1 m s 1 . What is the percentage uncertainty in the momentum of the object? A. 1% B. 6% C. 10% D. 20% Review Conceptual Example 8 as background for this problem. A loudspeaker is generating sound in a room. At a certain point, the sound waves coming directly from the speaker (without reflecting from... A snooker ball strikes a stationary ball. The second ball moves off sideways at 60 to the initial path of the first ball. Use the idea of conservation of momentum to explain why the first ball cannot... Review Conceptual Example 2 as an aid in solving this problem. An object is attached to the lower end of a 100-coil spring that is hanging from the ceiling. The spring stretches by 0.160 m. The... You and your team are exploring an antiquated research facility in the mountains of southern Argentina that had been abandoned in the 1960s. You come to a giant locked door that has no visible... Refer to Conceptual Example 2 as an aid in solving this problem. A 100-coil spring has a spring constant of 420 N/m. It is cut into four shorter springs, each of which has 25 coils. One end of a... You and your team are designing a tunable, single-tone, acoustic emitter. One end of a string is connected to a post on the top of a frictionless inclined plane. The string supports a mass at rest... Calculate the mean drift velocity of electrons in a copper wire of diameter 1.0 mm with a current of 5.0 A. The electron number density for copper is 8.5 10 28 m 3 . Review Conceptual Example 6 as an aid in understanding this problem. Consider the pump on the right side of Figure 11.10, which acts to reduce the air pressure in the pipe. The air pressure outside... A certain windmill produces an average of 0.50 MW of electrical power during the late evening hours when energy consumption is at a low (a four-hour span). An industrial capacitor (the BC125) has a... Review Conceptual Example 5 before attempting this problem. As the drawing shows, the length of a guitar string is 0.628 m. The frets are numbered for convenience. A performer can play a musical... Review Conceptual Example 11 before attempting to work this problem. The magnitude of each of the charges in Figure 18.20 is 8.60 10 12 C. The lengths of the sides of the rectangles are 3.00 cm and... A hydrogen atom (Z = 1) is in the third excited state, and a photon is either emitted or absorbed. Concepts: (i) What is the quantum number of the third excited state? (ii) When an atom emits a... A car is travelling round a bend when it hits a patch of oil. The car slides off the road onto the grass verge. Explain, using your understanding of circular motion, why the car came off the road. An astronomer is measuring the electromagnetic radiation emitted by two stars, which are both assumed to be perfect blackbody emitters. For each star she makes a plot of the radiation intensity per... Rays of light coming from the sun (a very distant object) are near and parallel to the principal axis of a concave mirror. After reflecting from the mirror, where will the rays cross each other at a... Show that an alternative equation for the centripetal acceleration is a = 2 r. Which of the following statements about effective nuclear charge for the outermost valence electron of an atom is incorrect? (i) The effective nuclear charge can be thought of as the true nuclear... The AsAs bond length in elemental arsenic is 2.48 . The ClCl bond length in Cl 2 is 1.99 . (a) Based on these data, what is the predicted AsCl bond length in arsenic trichloride, AsCl 3 , in which... An toy truck of mass 0.40 kg travels round a horizontal circular track of radius 0.50 m. It makes three complete revolutions every 10 seconds. Calculate: a. Its speed b. Its centripetal acceleration... The solubility of two slightly soluble salts of M 2+ , MA and MZ 2 , are the same, 4 10 -4 mol/L. (a) Which has the larger numerical value for the solubility product constant? (b) In a saturated... For each statement, indicate whether it is true or false. (a) The solubility of a slightly soluble salt can be expressed in units of moles per liter. (b) The solubility product of a slightly soluble... As shown in Figure 14.24, the first step in the heterogeneous hydrogenation of ethylene is adsorption of the ethylene molecule on a metal surface. One proposed explanation for the sticking of... a. Calculate the root-mean-square speed of helium molecules at room temperature and pressure. (Density of helium at room temperature and pressure = 0.179 kg m 3 .) b. Compare this speed with the... Which of these statements about alloys and intermetallic compounds is false? (a) Bronze is an example of an alloy. (b) Alloy is just another word for a chemical compound of fixed composition that is... Calculate the volume of 1 mole of ideal gas at a pressure of 1.01 10 5 Pa and at a temperature of 0 C. A cylinder contains 4.0 10 2 m 3 of carbon dioxide at a pressure of 4.8 10 5 Pa at room temperature. Calculate: a. The number of moles of carbon dioxide b. The mass of carbon dioxide. (Molar mass... A bar of gold-197 has a mass of 1.0 kg. Calculate: a. The mass of one gold atom in kg. b. The number of gold atoms in the bar c. The number of moles of gold in the bar. (An atom of gold contains 197... A piston/cylinder assembly contains 2 kg of liquid water at 20C and 300 kPa, as shown in Fig. P3.48. There is a linear spring mounted on the piston such that when the water is heated, the pressure... The following data are for a simple steam power plant as shown in Fig. P4.118. State 6 has x6 =0.92 and velocity of 200 m/s. The rate of steam flow is 25 kg/s, with 300 kW of power input to the pump.... A cylinder holds 140 m 3 of nitrogen at room temperature and pressure. Moving slowly, so that there is no change in temperature, a piston is pushed to reduce the volume of the nitrogen to 42 m 3 . a.... The power stroke in an internal combustion engine can be approximated with a poly tropic expansion. Consider air in a cylinder volume of 0.2 L at 7MPa, 1800 K, shown in Fig. P6.111. It now expands in... The solute in Problem 23-8 is initially dissolved in 80.0 mL of water. It is then extracted six times with 10.0-mL portions of chloroform. Find the fraction of solute remaining in the aqueous phase.... Buoyancy correction factor: mtrue/mread = 1.000 3244] [Interpolated density of water at 23.3 C: 0.997 468 9 g/mL] [HCl concentration at 20 C: 0.102343 M] Reagents: The molar mass and density of... The success of an airline depends heavily on its ability to provide a pleasant customer experience. One dimension of customer service on which airlines compete is on-time arrival. The file... Many service companies collect data via a follow- up survey of their customers. For example, to ascertain customer sentiment, Delta Air Lines sends an email to customers immediately following a... Consumer Research, Inc., is an independent agency that conducts research on consumer attitudes and behaviors for a variety of firms. In one study, a client asked for an investigation of consumer... Robs Market (RM) is a regional food store chain in the southwest United States. David White, Director of Business Intelligence for RM, would like to initiate a study of the purchase behavior of...
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