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At the end of a statistics course,110 students sit an examination. The marks are grouped into classes, as shown in the following table. It is believed that the mean for the population is 47.5. a.... The owner of a small ski hostel records the demand for rooms during high season. a. Show that the mean demand for rooms per night is 1.72. A test is to be carried out at the 1% significance level to... For each of the following distributions, write the table of expected values. a. b. c. 2 Explain the term partial pressure and explain why Daltons law is a limiting law. One end of a light, elastic string, of natural length 1.2m and modulus of elasticity 32N, is attached to a fixed point, B. A particle, P, of mass 1.5 kg, is then attached to the other end of the... What is the orbital angular momentum of an electron in the orbitals (a) 1s, (b) 3s, (c) 3d? Give the numbers of angular and radial nodes in each case. Weisman, Inc. uses activity-based costing as the basis for information to set prices for its six lines of seasonal coats. Compute the activity-based overhead rates using the following budgeted data... A survey asked people their working status, and coded the responses as follows: 1 = Working; 2 = With a job but not at work; 3 = Looking for work; 4 = Not working; 7 = Refused to answer; 9 = Dont... Consider the following hypothetical basketball records for Spelman and Morehouse Colleges. a. Give numerical evidence to support the claim that Spelman College has a better team than Morehouse... The states of Alabama, Alaska, Arizona, Arkansas, California, Colorado, and Connecticut have the following areas in square miles (land and water), with the areas listed in the same order as the... Pulse rates for adult females are normally distributed with a mean of 74.0 beats per minute (bpm) and a standard deviation of 12.5 bpm. Use the 68-95-99.7 rule to find the following values. a.... 8. Bins. I saw two frequency tables of airline passenger weights, one using bins that spanned 10-pound ranges (e.g. 101 to 110 nounds) and the second with bins that spanned 20-pound 109 of 449 I to... Consider the display in Figure 3.22 of median salaries of males and females in recent years. a. What general trends does the graph convey? b. Redraw the graph as a multiple line graph (with two... The molar absorptivity of the dye rhodamine 6G is about 10 5 L/mol cm at 540 nm. Estimate for a 10 3 M solution of this dye in ethanol. Consider a single molecule with an electronic transition at 530 nm that is exposed to a source having an energy density of 10 19 J/m 3 Hz at that wavelength. The transition dipole moment of the... Textbooks often use cacti and euphorbias (spurges) to illustrate convergent evolution because many euphorbias have globular, succulent bodies that strongly resemble those of cacti, yet the two... Discuss each of the following topics in class or review the topics on your own. Then write a brief but complete essay in which you summarize the main points. Please include formulas and graphs as... Standard addition. The U.S. Environmental Protection Agency sets guidelines for the level of contaminants in drinking water below which no adverse health effects are likely to occur. The limit for... (a) Use data in Appendix 11 to give a quantitative explanation why H 2 can be prepared from the reaction of Zn with dilute mineral acid, but not from Cu with a dilute acid. (b) The ion [H 13 O 6 ]+... With reference to Box 23.2, develop a qualitative bonding scheme for ( 5 -Cp) 2 Fe. Box 23.2. THEORY Box 23.2 Bonding in cyclopentadienyl complexes: -mode If all five C atoms of the cyclopentadienyl... Give an explanation for the following observations (part d assumes Box 29.2 has been studied): (a) Both haemoglobin and cytochromes contain haem-iron; (b) Cytochrome c oxidase contains more than one... Cells obtain nutrients from and deposit waste into _______. a. Blood b. Lymph vessels c. Each other d. Both a and b How do actin and myosin interact in a sarcomere to bring about muscle contraction? What roles do ATP and calcium play? Vasovist is the tradename of a Gd(III) complex which was the first intravascular contrast agent (see Box 4.3) approved in the EU for use in magnetic resonance angiography. Interactions between the... Iron is essential to all life forms. Assess the solubility of Fe in +2 and +3 oxidation states; combine this with likely stable oxidation state under normal conditions to assess the bioavailability... The existence of a maximum oxidation number of +6 for both uranium (Z = 92) and tungsten (Z = 74) prompted the placement of U under W in early periodic tables. When the element after uranium,... In the pulmonary circuit, the hearts _______ half pumps _______ blood to capillary beds inside the lungs; then _______ blood flows to the heart. a. Left; deoxygenated; oxygenated b. Right;... Give examples of situations when weather affected your or your familys life. Then do the same for climate. Box 6-1 Plants and People: Leaves, Food, and Death, describes several ways that leaves affect animals. What is the name of the toxic chemical in leaves of poison hemlock and death camas? In leaves of... Is it always easy to recognize that something is a living being rather than an inanimate object? Europa is a moon of Jupiter (see Box 1-2), and it is so far from the sun that there is not enough... What is an allele? Do all genes come in only one form such that every plant that has that gene has exactly the same nucleotide sequence? Look at the gene in FIGURE 16-26. How do the various alleles... How would the mean annual temperature of the Earth change if the average albedo of the Earth were 1) raised to 0.5 from its present value of about 0.3, and 2) lowered to 0.1? Now consider what will happen to the maximum elevations of the land when V-shaped valleys are chopped throughout the landmass, extending down to sea level. Assume that the valleys take up the entire... If it takes one second to write down each digit, how long will it take to write down all the numbers from 1 to 1,000? Slope stability. Consider a long linear hillslope with a slope angle of 25. It has soil that is 1 m thick, and a shear test on the soil reveals its internal angle of friction is 31, a cohesion... Consider the plot of landslide areas in Figure 10.37. Assess the slope of the straight-line fit to the data, and report the resulting probability density function for landslide area. Figure 10.37... Have you tried using the Plants and People Box 18-4 to key out plants? Couplet 6 is used to distinguish between beets and turnips and relies on a character that is very easy to assess. What character... In the northeastern fault block of the Bree Creek Quadrangle there is a hill that is capped by Helms Deep Sandstone overlying Rohan Tuff. In Problem 3.1 you determined the attitudes of these two... In Problems 2530, first estimate your answer and then calculate the exact answer. If your car gets 23 miles per gallon, how far can you go on 15 gallons of gas? MO diagrams for cyclic H N molecules are shown in Figure 6.1. The AO phases are shown for the lowest- and highest-energy MOs but not for the intermediate MOs. (a) Sketch out the intermediate MOs... What percentage ofsingle-walled carbon nanotubesin a typicalsynthesis batch will be semiconducting? Explain your answer. Calculate the volume of excavation in bank measure required for the basement shown in Figure 27. Excavation depths are in feet (meters). Figure 2-7: Which of the following pure compounds will exhibit hydrogen bonding? a) CH 3 CH 2 OH b) CH 2 O c) C 2 H 4 d) C 2 H 2 e) CH 3 OCH 3 f) CH 3 NH 2 g) C 3 H 8 h) NH 3 Identify the major product(s) for each of the following reactions. If any of the reactions do not yield a product, indicate no reaction. (a) (b) (c) (d) (e) (f) Br2 hv I2 I2 hv Identify the reagents you would use to convert 2-bromo-2-methylbutane into 3-methyl-1-butyne. Identify the reagents you would use to convert 1-pentene into a geminal dibromide (geminal indicates that both bromine atoms are connected to the same carbon atom). Identify which compounds below possess a molecular dipole moment and indicate the direction of that dipole moment: a. b. c. d. :i: i: .CI: II .C. .C. H. :: :Cl: . .C. .C. di: . CHO Predict the product of the following reaction. M 1) LIAID, 2) H20 Me Suggest an efficient synthesis for the following transformation: OH For each reaction below, draw the mechanism (curved arrows) and then predict which side of the reaction is favored under equilibrium conditions. (a) (b) (c) (d) H. Starting with acetylene as your only source of carbon atoms, propose a plausible synthesis for 1, 4-dioxane: 1,4-Dioxane Provide an IUPAC name for each of the following alcohols: a. The S N 2 reaction between a Grignard reagent and an epoxide works reasonably well when the epoxide is ethylene oxide. However, when the epoxide is substituted with groups that provide steric... Identify which two compounds below are constitutional isomers: (CH].C,H, (CH),c, (CH),, In each of the following transformations, identify whether the starting material has been oxidized, reduced, or neither. Try to determine the answer without calculating Oxidation states, and then use... Show how you would use a Grignard reaction to prepare each compound below. a. b. c. d. e. f. OH Using any compounds that have no more than two carbon atoms, identify a method for preparing each of the following compounds: a. b. c. d. Consider the following two dienes. When treated with HBr, one of these dienes yields four products, while the other diene yields only two products. Explain. Cylopentadiene reacts very rapidly in Diels-Alder reactions. In contrast, 1,3-cyclohexadiene reacts more slowly and 1,3-cycloheptadiene is practically unreactive. Can you offer an explanation for... Deduce the structure of a compound with molecular formula C 5 H 10 O that exhibits the following IR, 1 H NMR, and 13 C NMR spectra. Data from the mass spectrum are also provided. 100 Mass Spec. Data... There are many stereo-isomers of 1, 2, 3, 4, 5, 6-hexachlorocyclohexane. One of those stereo-isomers undergoes E2 elimination thousands of times more slowly than the other stereo-isomers. Identify... Consider the following [4+4] cycloaddition process. Would you expect this process to occur through a thermal or photochemical pathway? Justify your answer with MO theory. + Each of the following compounds does not participate as a diene in a Diels-Alder reaction. Explain why in each case. (a) (b) (c) (d) Under what conditions are H and U for a reaction involving gases and/or liquids or solids identical? Suggest reagents that would achieve the following transformation: CI CI CI Identify the reagents you would use to achieve each of the following transformations: (a) Conversion of all of the carbon atoms in bromoethane into CO 2 gas (b) Conversion of all of the carbon atoms... Compound A has molecular formula C 7 H 12 . Hydrogenation of compound A produces 2 methylhexane. Hydroboration-oxidation of compound A produces an aldehyde. Draw the structure of compound A, and draw... Consider the following reaction: a. Draw the mechanism of this reaction. b. What is the rate equation of this reaction? c. Draw an energy diagram of the reaction. H2SO, Heat OH Indicate whether you would use sodium ethoxide or potassium tert-butoxide to achieve each of the following transformations: a. b. c. d. Br Br Show that (C V /V) T = T( 2 P/ T 2 ) V When isopropylbenzene (cumene) is treated with NBS and irradiated with UV light, only one product is obtained. Propose a mechanism, and explain why only one product is formed. Br NBS hv Is the ratio of fugacity to pressure greater to or less than one if the attractive part of the interaction potential between gas molecules dominates? In each of the following cases identify the alkene that is expected to be more reactive toward acid-catalyzed hydration. a. b. 2-Methyl-2-butene or 3-methyl-1-butene or Identify the reagents that would be necessary to accomplish each of the transformations shown here: Br Identify the reagents you would use to achieve each of the following transformations: (a) (b) Predict the major product expected for each of the following reactions: (a) (b) (c) (d) (e) (f) ? XS HCI CI 1) xs NANH/NH3 2) H,0 CI Draw the major product(s) expected when each of the following alkynes is treated with aqueous acid in the presence of mercuric sulfate (HgSO 4 ): (a) (b) (c) (d) (e) One mole of H 2 O(l) is super cooled to 3.75C at 1 bar pressure. The freezing temperature of water at this pressure is 0.00C. The transformation H 2 O(l) H 2 O(s) is suddenly observed to occur. By... The Williamson ether synthesis cannot be used to prepare tert-butyl phenyl ether. a. Explain why this method cannot be used in this case. b. Suggest an alternative method for preparing tert-butyl... When 5-bromo-2, 2-dimethyl-1-pentanol is treated with sodium hydride, a compound with molecular formula C 7 H 14 O is obtained. Identify the structure of this compound. NaH, Br -40 Predict the products obtained when 1-pentyne reacts with each of the following reagents: (a) H 2 SO 4 , H 2 O, HgSO 4 (b) 9-BBN followed by H 2 O 2 , NaOH (c) Two equivalents of HBr (d) One... Draw a plausible mechanism for the following transformation: , [H2SO4] Propose a plausible mechanism for the reaction below: [H2SO4] N- - . -N. Lindane (hexachlorocyclohexane) is an agricultural insecticide that can also be used in the treatment of head lice. Draw both chair conformations of lindane. CI CI 'CI CI I Lindane Which of the following compounds has the larger dipole moment? Explain your choice: CHCl 3 or CBrCl 3 What reagents would you use to prepare each of the following thiols: a. b. c. SH SH Propose an efficient synthesis for each of the following transformations: (a) (b) (c) OH Draw curved arrows for each step of the following mechanism: . . -CH;So --S0 NO2 Draw curved arrows for each step of the following mechanism: : : : 0: . : : -O: : - : : : : H20 - Predict the product(s) for each reaction below: (a) (b) (c) (d) * OMe * OMe Predict the major product for each of the following intramolecular reactions: (a) (b) [H*] -2 NH2 [H] NH2 -H20 Identify the reactants that you would use to make each of the following imines: (a) (b) (c) N. There are four isomers with molecular formula C 4 H 9 Cl. Only one of these isomers (compound A) has a chirality center. When compound A is treated with sodium ethoxide, three products are formed:... Identify the reactants that you would use to make each of the following imines: (a) (b) (c) N. Identify the reactants that you would use to make each of the following enamines: (a) (b) (c) -N Predict the major product for each of the following reactions: (a) (b) (c) (d) 1) LAH 2) H20 H NABH4, Draw a plausible mechanism for the following transformation: -NH2 [H,SO] NH2 [-H,0] Benzene was treated with isopropyl chloride in the presence of aluminum trichloride under conditions that favor dialkylation. Draw the major product expected from this reaction. Predict the major product of each reaction below: (a) (b) (c) 1) EtMgBr 2) H20 :? H. 1) PhMgBr 2) H20 Propose an efficient synthesis for each of the following transformations: (a) (b) (c) (d) (e) (f) (g) -OH
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