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Do you think that propanedial, shown in the margin, can be easily prepared by a simple Claisen condensation? Why or why not? HCH,CH Propanedial Write out, in full detail, the mechanism of the Michael addition of malonic ester to 3-buten-2-one in the presence of ethoxide ion. Be sure to indicate all steps that are reversible. Does the overall... Based on the mechanism presented for the Pd-catalyzed reaction of a halobenzene with hydroxide ion, write out a reasonable mechanism for the Pd-catalyzed reaction of Problem 38(a). Problem 38(a) (a)... Two of the following four compounds are more acidic than CH 3 OH (i.e., two of these have K a greater than methanol). Which ones? (a) A and B; (b) B and C; (c) C and D; (d) D and A; (e) D and B.... Arrange the following compounds in order of increasing acidity. Estimate pK a values for each. (a) (b) CH 3 CO 2 H (c) CH 3 OH (d) (e) CH 3 CHO (f) (g) CH 3 O 2 CCH 2 CO 2 CH 3 (h) CH 3 O 2 CCO 2 CH 3 Which one of the following statements is true about the oxacyclohexane conformer of the sugar -D-(1)-glucopyranose? (a) One OH group is axial, but all remaining substituents are equatorial. (b) The... Rank the following compounds in increasing order of basicity: water, hydroxide, pyridine, pyrrole, ammonia. The astronomical unit equals the mean distance between the earth and the sun. This distance is 150,000,000 km, which is precise to three significant figures. Express this in scientific notation to... How many of the following are found in 15.0 kmol of xylene (C 8 H 10 )? (a) kg C 8 H 1 ; (b) mol C 8 H 1 ; (c) lb-mole C 8 H 1 ; (d) mol (g-atom) C; (e) mol H; (f) g C; (g) g H; (h) molecules of C 8... Suggest a synthesis of each of the following -dicarbonyl compounds by Claisen or Dieckmann condensations. (a) (b) (c) (d) (e) (f) (g) -CH,CCHCOCH,CH3 Devise a preparation of each of the following ketones by using the acetoacetic ester synthesis. (a) (b) (c) (d) OCH,CH3 Devise a synthesis for each of the following four compounds by using the malonic ester synthesis. (a) (b) (c) (d) HO A rigid 6.00-liter vessel contains 4.00 L of liquid water in equilibrium with 2.00 L of water vapor at 25C. Heat is transferred to the water by means of an immersed electrical coil. The volume of the... Use the Michael Addition methods , with other reactions if necessary, to synthesize each of the following compounds. In each case, your starting materials should include one aldehyde or ketone and... Carbonic acid, H 2 CO 3 , is commonly assumed to be an unstable compound that easily decomposes into a molecule of water and a molecule of carbon dioxide: H 2 CO 3 H 2 O + CO 2 . Indeed, the... Give the likely products of each of the following reactions. All are carried out in the pre sence of a Pd catalyst, a ligand for the metal such as a phosphine, and heat. (a) (b) Br + :CH(CO2CH2CH3)2 Various uses for nitric acid are given in Problem 6.43, along with information about how this important chemical is synthesized industrially. The key reactions are oxidations of ammonia to nitric... If 20.0 mL of a 0.10 M NaOH solution is added to a 30.0- mL sample of a 0.10 M weak acid, HA, what is the pH of the resulting solution? (K a = 1.8 10 5 for HA) a. 2.87 b. 2.74 c. 4.74 d. 5.05 e. 8.73 Identify each of the following compounds as a primary, secondary, or tertiary amine, or as an amide. a. b. CH 3 CH 2 NHCH 2 CH 3 CH;NH What change or changes in the state of a gas bring about each of the following effects? (a) The number of impacts per unit time on a given container wall increases. (b) The average energy of impact... Explain why the d xy , d xz , and orbitals lie lower in energy than the d z2 and d x2-y2 orbitals in the presence of an octahedral arrangement of ligands about the central metal ion. Certain solid substances, known as hydrated compounds, have well-defined molecular ratios of water to some other species. For example, calcium sulfate dihydrate (commonly known as gypsum, (CaSO 4 2H... A liquid-phase chemical reaction A ! B takes place in a well-stirred tank. The concentration of A in the feed is C A0 (mol/m 3 ), and that in the tank and outlet stream is CA (mol/m 3 ). Neither... Which of the following are correct? Correct any false statements. a. A conjugated diene with an even number of double bonds undergoes conrotatory ring closure under thermal conditions. b. A... Cyclobutadiene (below) is like benzene in that it has alternating single and double bonds in a ring. However, its bonds are not the same length, the double bonds being shorter than the single bonds;... An evaporationcrystallization process of the type described in Example 4.5-2 is used to obtain solid potassium sulfate from an aqueous solution of this salt. The fresh feed to the process contains... Without consulting tables, arrange the following compounds in order of decreasing acidity: Pentane 1-Pentene 1-Pentyne 1-Pentanol Mammalian cells can be cultured for a variety of purposes, including synthesis of vaccines. They must be maintained in growth media containing all of the components required for proper cellular... How many 13 C NMR signals would you predict for (a) Naphthalene, (b) Anthracene, (c) Phenanthrene, (d) Pyrene? In addition to a signal downfield, the 1 H NMR spectrum of trans-15,16-dimethyldihydro- tice pyrene has a signal far upfield at -4.2. Account for the presence of this upfield signal. Carbon nanotubes (CNT) are among the most versatile building blocks in nanotechnology. These unique pure carbon materials resemble rolled-up sheets of graphite with diameters of several nanometers... A slurry contains crystals of copper sulfate pentahydrate [CuSO45H2O(s), specific gravity = 2.3] suspended in an aqueous copper sulfate solution (liquid SG = 1.2). A sensitive transducer is used to... Carbon nanotubes (CNT) are among the most versatile building blocks in nanotechnology. These unique pure carbon materials resemble rolled-up sheets of graphite with diameters of several nanometers... Air in industrial plants is subject to contamination by many different chemicals, and companies must monitor ambient levels of hazardous species to be sure they are below limits specified by the... A spray-drying operation similar to that described in Problem 5.23 is used by the pharmaceutical industry. Acetaminophen is an active pharmaceutical ingredient (API) that can be produced in powdered... Ammonia is one of the chemical constituents of industrial waste that must be removed in a treatment plant before the waste can safely be discharged into a river or estuary. Ammonia is normally... The current global reliance on fossil fuels for heating, transportation, and electric power generation raises concerns regarding the release of CO 2 and CH 4 , which are greenhouse gases thought to... You have been assigned the task of measuring the equilibrium constant for the reaction N 2 O 4 2NO 2 as a function of temperature. To do so, you evacuate a rigid 2-liter vessel equipped with a... When a flammable liquid (e.g., gasoline) ignites, the substance actually burning is vapor generated from the liquid. If the concentration of the vapor in the air above the liquid exceeds a certain... The IR, NMR, and mass spectra are provided for an organic compound. (a) Consider each spectrum individually, and tell what characteristics of the molecule are apparent from that spectrum. (b) Propose... Estimate the vapor pressure of acetone (mm Hg) at 50C (a) from data in Perrys Chemical Engineers Handbook (Footnote 1) and the ClausiusClapeyron equation, (b) from the Antoine equation using... A liquid mixture contains N components (N may be any number from 2 to 10) at pressure Pmm Hg. The mole fraction of the ith component is xi(i = 1; 2; ... ;N), and the vapor pressure of that component... A 12.1-g sample of Na 2 SO 3 is mixed with a 14.6-g sample of MgSO 4 . What is the total mass of oxygen present in the mixture? Consider the jar of jelly beans in the photo. To get an estimate of the number of beans in the jar you weigh six beans and obtain masses of 3.15, 3.12, 2.98, 3.14, 3.02, and 3.09 g. Then you weigh... A fuel cell is an electrochemical device in which hydrogen reacts with oxygen to produce water and DC electricity. A 1-watt proton-exchange membrane fuel cell (PEMFC) could be used for portable... Recovery of a solvent vapor from a gas stream by condensation can be achieved by cooling the gas, by compressing it, or by a combination of these operations. The greater the compression, the less... Various amino acids have utility as food additives and in medical applications. They are often synthesized by fermentation using a specific microorganism to convert a substrate (e.g., a sugar) into... Nitric acid is a chemical intermediate primarily used in the synthesis of ammonium nitrate, which is used in the manufacture of fertilizers. The acid also is important in the production of other... Serine (Ser, molecular weight=105.1 g/mol) is a nonessential amino acid produced by fermentation. As with many other fermentation products, substantial downstream processing is required to meet... In this problem you will use a spreadsheet to create a Txy diagram for the benzene-chloroform system at 1 atm. Once the spreadsheet has been created, it can be used as a template for vaporliquid... An aqueous waste stream leaving a process contains 10.0 wt% sulfuric acid and 1 kg nitric acid per kg sulfuric acid. The flow rate of sulfuric acid in the waste stream is 1000 kg/h. The acids are... A 0.60-kg metal sphere oscillates at the end of a vertical spring. As the spring stretches from 0.12 to 0.23 m (relative to its unstrained length), the speed of the sphere decreases from 5.70 to 4.80... Various amino acids have utility as food additives and in medical applications. They are often synthesized by fermentation using a specific microorganism to convert a substrate (e.g., a sugar) into... An object is situated at a known distance in front of a convex mirror whose focal length is also known. A friend of yours does a calculation that shows that the magnification is 2. After some... Define a system and simplify the open-system energy balance (Equation 7.4-15) for each of the following cases. State when possible whether nonzero heat and shaft work terms are positive or negative.... An object is placed at a known distance in front of a mirror whose focal length is also known. You apply the mirror equation and find that the image distance is a negative number. This result tells... Suppose that you hold up a small convex mirror in front of your face. Which answer describes the image of your face? (a) Virtual, inverted (b) Virtual, upright (c) Virtual, enlarged (d) Real,... During a period of relative inactivity, the average rate of transport of enthalpy by the metabolic and digestive waste products leaving the body minus the rate of enthalpy transport by the raw... Assume that the following reaction occurs at constant pressure: 2Al(s) + 3Cl 2 (g)2 AlCl 3 (s) (a) If you are given H for the reaction, what additional information do you need to determine E for the... The following diagram shows a simplified version of how a refrigerator works: In a liquid receiver 1 , a liquid refrigerant (any one of a number of halogenated hydrocarbons such as CCl 2 F 2 ) is... (a) Does metallic character increase, decrease, or remain unchanged as one goes from left to right across a row of the periodic table? (b) Does metallic character increase, decrease, or remain... Water is to be pumped from a lake to a ranger station on the side of a mountain (see figure). The length of pipe immersed in the lake is negligible compared to the length from the lake surface to the... You have a gas at 25 C confined to a cylinder with a movable piston. Which of the following actions would double the gas pressure? (a) Lifting up on the piston to double the volume while keeping the... Your next-door neighbor, Josephine Rackstraw, surprised her husband last January by having a hot tub installed in their back yard while he was away on an ice-fishing trip. It surprised him, all... It takes 4 h 39 min for a 2.00-mg sample of radium-230 to decay to 0.25 mg. What is the half-life of radium-230? A flask contains 49.8 mL of 0.150 M Ca(OH) 2 (calcium hydroxide). How many milliliters of 0.500 M Na 2 CO 3 (sodium carbonate) are required to react completely with the calcium hydroxide in the... A stream of carbon monoxide flowing at 300 kg/min is cooled from 450C to 50C at a low pressure. (a) Calculate the required rate of cooling (kW), using the enthalpy function of APEx. Check the... A sample of nitrogen gas at 17C and 760 mmHg has a volume of 8.06 mL. What is the volume at 9C and 1 atm of pressure? Consider the possibility of converting carbon dioxide to carbon monoxide by the endothermic reaction CO 2( g) + H 2( g) CO(g) + H 2 O(g) Is a high or a low temperature more favorable to the... Lauryl alcohol, C 12 H 25 OH, is prepared from coconut oil; it is used to make sodium lauryl sulfate, a synthetic detergent. What is the molality of lauryl alcohol in a solution of 17.1 g lauryl... Calculate the lattice energy of potassium fluoride, KF, using the BornHaber cycle. Use thermodynamic data from Appendix C to obtain the enthalpy changes for each step. What is the pH at the equivalence point when 22 mL of 0.20 M hydroxylamine is titrated with 0.10 M HCl? A quantity of strong acid is added to pure water to give a solution that is 0.100 M H + . Calculate Q for the following reaction just as the H + ion is added and before equilibrium is established. H... Ever wonder why espresso costs much more per cup than regular drip coffee? Part of the reason is the expensive equipment needed to brew a proper espresso. A high-powered burr grinder first shears the... Figure P3.11 shows three physical situations. Show the possible process in a Pv diagram. R-410a (a) (b) (c) FIGURE P3.11 A gas stream containing n-hexane in nitrogen with a relative saturation of 90% is fed to a condenser at 75C and 3.0 atm absolute. The product gas emerges at 0C and 3.0 atm at a rate of 746.7 m 3 /h.... Polyvinylpyrrolidone (PVP) is a polymer product used as a binding agent in pharmaceutical applications as well as in personal-care items such as hairspray. In the manufacture of PVP, a spray-drying... Freeze drying is a technique for dehydrating substances at low temperatures, thereby avoiding the degradation that may accompany heating. The material to be dried is cooled to a temperature at which... A piece of steel has a conductivity of k = 15 W/mK and a brick has k =1W/mK. How thick a steel wall will provide the same insulation as a 10-cm-thick brick? An ideal gas in a piston/cylinder is heated with 2 kJ during an isothermal process. How much work is involved? An ideal gas in a piston/cylinder is heated with 2 kJ during an isobaric process. Is the work positive, negative, or zero? Humid air is enclosed in a 2.00-liter flask at 40C. The flask is slowly cooled. When the temperature reaches 20C, drops of moisture become visible on the flask wall. Although the pressure in the... Aballoon behaves so that the pressure isP=C 2 V1/3 and C 2 = 100 kPa/m. The balloon is blown up with air from a starting volume of 1 m 3 to a volume of 4 m 3 . Find the final mass of air, assuming it... A nitrogen gas goes through a polytropic process with n = 1.3 in a piston/cylinder. It starts out at 600 K, 600 kPa and ends at 800 K. Is the work positive, negative, or zero? A small pharmaceutical firm plans to manufacture a new drug and has hired you as a consultant to design a condenser to remove the drug from a gasvapor mixture. The mixture, which contains 20 mole% of... Give the phase and the specific volume for the following: a. R-410a, T =25 F, P = 30 lbf/in. 2 b. R-410a, T =25 F, P = 40 lbf/in. 2 c. H 2 O, T = 280 F, P = 35 lbf/in. 2 d. NH 3 , T = 60 F, P = 15... A small pharmaceutical firm plans to manufacture a new drug and has hired you as a consultant to design a condenser to remove the drug from a gasvapor mixture. The mixture, which contains 20 mole% of... Wet wood chips are dried in a continous rotary dryer that operates at atmospheric pressure. The chips enter at 19C with a water content of 40 wt% and must leave with a moisture content of less than... A small pharmaceutical firm plans to manufacture a new drug and has hired you as a consultant to design a condenser to remove the drug from a gasvapor mixture. The mixture, which contains 20 mole% of... Sodium hydroxide is dissolved in enough water to make up a 20.0 mole% solution. (a) If the NaOH and water are initially at 77F (25C), how much heat (Btu/lb product solution) must be removed for the... A piston/cylinder arrangement with a linear spring similar to Fig. P3.105 contains R-134a at 15C, x= 0.4 and a volume of 0.02m 3 . It is heated to 60C, at which point the specific volume is 0.030 02... A piston/cylinder arrangement of initial volume 0.025 m 3 contains saturated water vapor at 180C. The steam now expands in a polytropic process with exponent n = 1 to a final pressure of 200 kPa... A small pharmaceutical firm plans to manufacture a new drug and has hired you as a consultant to design a condenser to remove the drug from a gasvapor mixture. The mixture, which contains 20 mole% of... Spray cooling is a technique for cooling and either humidifying or dehumidifying air by contacting it with a spray of liquid water. Water in a piston/cylinder (Fig. P3.174) is at 101 kPa, 25C, and mass 0.5 kg. The piston rests on some stops, and the pressure should be 1000 kPa to float the piston. We now heat the water, so the... Spray cooling is a technique for cooling and either humidifying or dehumidifying air by contacting it with a spray of liquid water. Formaldehyde is produced by decomposing methanol over a silver catalyst: To provide heat for this endothermic reaction, some oxygen is included in the feed to the reactor,leading to the partial... Spray cooling is a technique for cooling and either humidifying or dehumidifying air by contacting it with a spray of liquid water. A fuel gas is known to contain methane, ethane, and carbon monoxide. A sample of the gas is charged into an initially evacuated 2.000-liter vessel at 25C and 2323mm Hg absolute. The vessel is weighed... A flow of 1 kg/s carbon dioxide at 1600 K, 100 kPa is mixed with a flow of 2 kg/s water at 800 K, 100 kPa, and after the mixing it goes through a heat exchanger, where it is cooled to 500 K by a 400...
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