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Predict the major product for each of the following E2 reactions: a. b. c. d. NaOH Br NaOH Br For each pair of the following compounds identify which compound would react more rapidly in an E2 reaction: a. b. CI .CI Br Br Consider the following sequence of reactions, and identify the structures of compounds A, B, and C. Mg Compound A (CeH11Br) Compound B 1) 2) H20 H,SO4 Compound C Heat Consider the following sequence of reactions, and identify the reagents ah. H. - ob-o - Br Starting with 1-butanol, show the reagents you would use to prepare each of the following compounds. a. b. c. d. e. H. . A 1.75 mole sample of an ideal gas is compressed isothermally from 62.0 L to 19.0 L using a constant external pressure of 2.80 atm. Calculate q, w, U, and H. Two ideal gas systems undergo reversible expansion under different conditions starting from the same P and V. At the end of the expansion, the two systems have the same volume. The pressure in the... Propose a plausible mechanism for each of the following transformations. a. b. 1) MeMgBr 2) H20 1) Excess MeMgBr 2) H20 Propose a plausible synthesis for each of the following transformations: a. b. c. d. e. f. g. h. i. j. k. l. m. n. o. p. q. r. s. H. Provide an IUPAC name for each of the following compounds. a. b. c. d. e. I Show what reagents you would use to prepare each of the following ethers via a Williamson ether synthesis, and explain your reasoning. a. b. c. OMe Draw a Lewis structure for a compound with molecular formula C 4 H 11 N in which three of the carbon atoms are bonded to the nitrogen atom. What is the geometry of the nitrogen atom in this compound?... Draw two constitutional isomers that have molecular formula C 3 H 7 Cl. Starting with benzene and using any other necessary reagents of your choice, design a synthesis for each of the following compounds. Each compound has a Br and one other substituent that we did not... Draw all constitutional isomers that have molecular formula C 4 H 10 O? Identify which two compounds shown here have the same degree of unsaturation. C 3 H 8 O C 3 H 5 ClO 2 C 3 H 5 NO 2 C 3 H 6 Identify all of the products formed when the compound below is treated with aqueous acid: N- excess H,O+ Predict the major product(s) for each reaction below. (a) (b) (c) 1) LAH 2) , 1) PhMgBr 2) H,0 Draw the expected isotope pattern that would be observed in the mass spectrum of CH 2 BrCl. In other words, predict the relative heights of the peaks at M, M + 2, and M + 4. A 1.75 mole sample of Ar undergoes an isothermal reversible expansion from an initial volume of 2.00 L to a final volume of 85.00 L at 310. K. Calculate the work done in this process using the ideal... Draw all significant resonance structures for each of the following compounds: a. b. c. d. e. f. g. h. i. j. k. l. . z: N. For each of the following compounds, identify all groups that would be considered substituents, and then indicate how you would name each substituent. (a) (b) (c) (d) (e) (f) (g) For each of the following pairs of compounds, identify the higher boiling compound and justify your choice: a. b. A newly developed substance that emits 250. W of photons with a wavelength of 325 nm is mounted in a small rocket initially at rest in outer space such that all of the radiation is released in the... (R)-Limonene is found in many citrus fruits, including oranges and lemons: For each of the following compounds identify whether it is (R)-limonene or its enantiomer, (S)-limonene: a. b. c. d. Identify the reagents you would use to achieve the following transformation: Identify the reagents you would use to accomplish each of the following transformations: (a) (b) (c) (d) (e) (f) (g) (h) OH Br The sex attractant of the codling moth gives an IR spectrum with a broad signal between 3200 and 3600 cm -1 and two signals between 1600 and 1700 cm -1 . In the mass spectrum of this compound, the... How many signals do you expect in the 13 C NMR spectrum of each of the following compounds? a. b. c. d. Br Propose a plausible mechanism for the following transformation. NaOH, H20 Heat Determine the constitution of the compounds with the following molecular formulas: (a) CH 4 O (b) CH 3 Cl (c) C 2 H 6 (d) CH 5 N (e) C 2 F 6 (f) C 2 H 5 Br (g) C 3 H 8 Consider the structure of lysergic acid diethylamide (LSD), a potent hallucinogen containing three nitrogen atoms. One of these three nitrogen atoms is significantly more basic than the other two.... Glutaraldehyde is a germicidal agent that is sometimes used to sterilize medical equipment too sensitive to be heated in an autoclave. In mildly acidic conditions, glutaraldehyde exists in a cyclic... Predict the major product(s) obtained when each of the following compounds undergoes hydrolysis in the presence of H 3 O + : (a) (b) (c) (d) z- z: Draw a plausible mechanism for each of the following transformations: (a) (b) (c) HJo+ N' H. Z H2N. H. Predict the major product(s) for each of the following reactions: (a) (b) (c) (d) (e) (f) CH NH2 [H*] (-H20) 1) PhMgBr 2) H20 How did Stern and Gerlach conclude that the operator measure the z component of the magnetic moment of an Ag atom has only two eigenfunctions with eigenvalues that have the same magnitude and... For each compound below, identify which position(s) is/are most likely to undergo an electrophilic aromatic substitution reaction. (a) (b) (c) (d) (e) (f) (g) (h) (i) CH3 NO2 O,N. CH3 O,N NO2 Nitrogen and oxygen do not absorb infrared radiation and are therefore not greenhouse gases. Why is this the case? When acetic acid is treated with isotopically labeled water ( 18 O, shown in red) in the presence of a catalytic amount of acid, it is observed that the isotopic label becomes incorporated at both... The rotational constant for 14 N 2 determined from microwave spectroscopy is 1.99824 cm 1 . Calculate the bond length in 14 N 2 to the maximum number of significant figures consistent with this... The rotational constant for 7 Li 19 F determined from microwave spectroscopy is 1.342583 cm 1 . The atomic masses of 7 Li and 19 F are 7.00160041 and 18.9984032 amu, respectively. Calculate the bond... If the vibrational potential is not harmonic, the force constant is not independent of degree of stretching or compression of a molecule. Using the relation k effective = (d 2 V(x)/dx 2 ), derive an... Pivampicillin is a penicillin prodrug: The prodrug ester moiety (in red) enables a more rapid delivery of the prodrug to the bloodstream, where the ester moiety is subsequently hydrolyzed by enzymes,... Calculate the wave number corresponding to the most and least energetic spectral lines in the Lyman, Balmer, and Paschen series for the hydrogen atom. Are the two PT phase diagrams below likely to be observed for a pure substance? If not, explain all features of the diagram that will not be observed. a. b. Liquid Vapor Solid Solid II Liquid Solid... A weak acid has a dissociation constant of K a = 2.50 10 2 . a. Calculate the degree of dissociation for a 0.093m solution of this acid using the DebyeHckel limiting law. b. Calculate the degree of... Ions with a single electron such as He + , Li 2+ , and Be 3+ are described by the H atom wave functions with Z/a 0 substituted for 1/a 0 , where Z is the nuclear charge. The 1s wave function becomes ... The energy levels for ions with a single electron such as He + , Li 2+ , and Be 3+ are given by E n = Z 2 e 2 / (8 0 a 0 n 2 ), n = 1, 2, 3, 4, . . . Calculate the ionization energies of H, He+,... Why does the effective nuclear charge for the 1s orbital increase by 0.99 in going from oxygen to fluorine but only increases by 0.65 for the 2p orbital? Show using an example that the following two formulations of the Pauli exclusion principle are equivalent: a. Wave functions describing a many-electron system must change sign under the exchange of... The absorption spectrum of the hydrogen atom shows lines at 5334, 7804, 9145, 9953, and 10,478 cm 1 . There are no lower-frequency lines in the spectrum. Use the graphical methods discussed in... Why does the Doppler effect lead to a shift in the wavelength of a star, but to a broadening of a transition in a gas? In the previous section, we learned how to use malonic ester as a starting material in the preparation of substituted carboxylic acids (the malonic ester synthesis). That method employed a step in... Without invoking equations, explain why the energy of the triplet state is lower than that of the singlet state for He in the 1s 1 2s 1 configuration. Write the Slater determinant for the ground-state configuration of Be. Why is the total energy of a many-electron atom not equal to the sum of the orbital energies for each electron? How can you tell if one basis set is better than another in calculating the total energy of an atom? Give examples of AOs for which the overlap reaches its maximum value only as the internuclear separation approaches zero in a diatomic molecule. Also give examples of AOs for which the overlap goes... Nitriles undergo alkylation at the α position much like ketones undergo alkylation at the α position. The α position of the nitrile is first deprotonated to... The total energy of a molecule is lowered if the orbital energy of the anti-bonding MO is negative, and raised if the orbital energy of the anti-bonding MO is positive. The zero of energy is the... Explain why the nodal structures of the 1 g MOs in H 2 and F 2 differ. Using a Gabriel synthesis, propose an efficient synthesis for each of the following transformations. In each case, you will need to use reactions from previous chapters to convert the starting... Calculate the value for the coefficients of the AOs in Example Problem 23.4 for S 12 = 0.45. How are they different from the values calculated in that problem for S 12 = 0.3? Can you offer an... Calculate the dipole moment of HF for the bonding MO in Equation (23.33). Use the method outlined in Section 23.8 to calculate the charge on each atom. The bond length in HF is 91.7 pm. The... Phencyclidine (PCP) was originally developed as an anesthetic for animals, but it has since become an illegal street drug because it is a powerful hallucinogen. Treatment of PCP with excess methyl... The bond dissociation energies of the species NO, CF , and CF + follow the trend CF + > NO > CF . Explain this trend using MO theory. Show that the determinantal property used in the discussion of localized and delocalized orbitals in Section 24.6 is correct. ya + c a la b yb + d 9. Explain why only two peaks are observed in the infrared spectrum of methane although six of the nine normal modes are infrared active. Can a molecule with C 3 h symmetry have a dipole moment? Give an example of a molecule with this symmetry and explain your reasoning. Can a molecule with D 2 h symmetry have a dipole moment? Give an example of a molecule with this symmetry and explain your reasoning. What is the difference between a symmetry element and a symmetry operation? Consider the case of 10 oscillators and eight quanta of energy. Determine the dominant configuration of energy for this system by identifying energy configurations and calculating the corresponding... The 1 H 35 Cl molecule can be described by a Morse potential with D e = 7.41 10 -19 J. The force constant k for this molecule is 516 N m 1 and v = 8.97 10 13 s 1 . a. Calculate the lowest four... How do the results shown in Figure 20.10 differ from the predictions of the Bohr model of the H atom? Figure 20.10 1s 2p 2s d 3s d 3s 2p 2s 1s 10 15 20 rlag Radial distribution function (Challenging) Building on the concept of equipartition, demonstrate that for any energy term of the form ax 2 , where α is a constant, the contribution to the internal energy is equal... Determine the standard molar Gibbs energy for 35 Cl 35 Cl, where v = 560. cm 1 , B = 0.244 cm 1 , and the ground electronic state is non-degenerate. The exact energy of a ground-state He atom is 79.01 eV. Calculate the correlation energy and the ratio of the correlation energy to the total energy for He using the results in Table 21.1. TABLE 21.1... Why is the stoichiometry of a reaction generally not sufficient to determine reaction order? What is the difference between the order of a reaction with respect to a given species and the overall order? What is an elementary chemical step, and how is one used in kinetics? What is the difference between chemical and physical methods for studying chemical kinetics? Consider the molecular electrostatic potential map for the BH 3 molecule shown here. Is the hydrogen atom (shown as a white sphere) an electron acceptor or an electron donor in this molecule? One issue confronting the use of 14 C decay to date materials is that of obtaining a standard. One approach to this issue is found in the field of dendrochronology, or using tree rings to determine... For a type II second-order reaction, the reaction is 60% complete in 60 seconds when [A] 0 = 0.1 M and [B] 0 = 0.5 M. a. What is the rate constant for this reaction? b. Will the time for the reaction... Identify the molecular orbitals for F 2 in the images shown here in terms of the two designations discussed in Section 23.7. The molecular axis is the z axis, and the y axis is tilted slightly out of... An experiment is performed on the branching reaction depicted in the text. Two things are determined: (1) The yield for B at a given temperature is found to be 0.3, and (2) the rate constants are... A standard rule of thumb for thermally activated reactions is that the reaction rate doubles for every 10 K increase in temperature. Is this statement true independent of the activation energy... Why does the list of elements for the D 6h group in Table 27.2 not list the elements C 2 6 , C 3 6 , and C 4 6 ? Selected Point Groups and Their Elements Symmetry Elements TABLE 27.2 Example Molecule... Draw the nucleoside formed from each of the following pairs of compounds and name the nucleoside: (a) 2-Deoxy-d-ribose and adenine (b) d-Ribose and guanine Why does the list of elements for the D 6h group in Table 27.2 not list the elements S 2 6 , S 3 6 , and 6? Selected Point Groups and Their Elements Symmetry Elements TABLE 27.2 Example Molecule... Use the 3 3 matrices for the C 2v group in Equation (27.3) to verify the group multiplication table for the following successive operations: a. v v b. v C 2 c. C 2 C 2 Draw a mechanism for the biosynthesis of α-farnesene starting with dimethylallyl pyrophosphate and isopentenyl pyrophosphate. a-Farnesene Use the 3 à 3 matrices for the C 2v group in Equation (27.2) to verify the associative property for the following successive operations: a. b. ,(6,C2) = (6,6-)C () = 6,(2) %3D Use the logic diagram of Figure 27.2 to determine the point group for allene. Indicate your decision-making process as was done in the text for NH3 1. linear? 2. C n axis? 3. more than 1C n axis? 4.... Use the logic diagram of Figure 27.2 to determine the point group for the planar molecule cisHBrC ¡ CClH. Indicate your decision-making process as was done in the text for NH 3 . a. linear? b.... CH 4 belongs to the T d point group with the following symmetry elements: E, 4C 3 , 4C 2 3 , 3C 2 , 3S 4 , 3S 3 4 , and 6Ï. Make a drawing similar to Figure 27.1 showing these elements. C2, S.... Four bases (A, C, T, and G) appear in DNA. Assume that the appearance of each base in a DNA sequence is random. a. What is the probability of observing the sequence AAGACATGCA? b. What is the... The natural abundance of 13 C is roughly 1%, and the abundance of deuterium ( 2 H or D) is 0.015%. Determine the probability of finding the following in a mole of acetylene: a. H- 13 C- 13 C-H b. D-... The lowest four energy levels for atomic vanadium (V) have the following energies and degeneracies: What is the contribution to the average energy from electronic degrees of freedom for V when T =...
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