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1 Million+ Step-by-step solutionsmath books Q:A certain organic compound was found on combustion analysis toA certain organic compound was found on combustion analysis to contain 84% carbon and 6c/c hydrogen (C = 12.0, H = 1.00). A molecular formula for the compound could be
(a) CH4O
(b) C6H14O2
(c) C7H16
(d) C6H10
(e) C14H22
Q:The compound has a formal charge of (a) -1 on N (b)The compound
The compound 
has  a formal charge of 
(a) -1 on N	 
(b)

has a formal charge of
(a) -1 on N
(b) +2 on N
(c) -1 on Al
(d) +1 on Br
(e) None of the above

Q:The arrow in the structure in the margin points toThe arrow in the structure in the margin points to a bond that is formed by
(a) Overlap of an s orbital on H and an sp2 orbital on C
(b) Overlap of an s orbital on H and an sp orbital on C
(c) Overlap of an s orbital on H and an sp3 orbital on C
(d) None of the above
Q:Which compound has bond angles nearest to 120°? (a) O =Which compound has bond angles nearest to 120°?
(a) O = C = S
(b) CHI3
(c) H2C = O
(d) H-C=C-H
(e) CH4
Q:The pair of structures that are resonance hybrids is (a)The pair of structures that are resonance hybrids is
(a)
The pair of structures that are resonance hybrids is  
(a)

(b)

The pair of structures that are resonance hybrids is  
(a)

(c)

The pair of structures that are resonance hybrids is  
(a)

(d)

The pair of structures that are resonance hybrids is  
(a)Q:Draw a Lewis structure for each of the following moleculesDraw a Lewis structure for each of the following molecules and assign charges where appropriate. The order in which the atoms are connected is given in parentheses.
(a) C1F
(b) BrCN
(c) SOC12(C1SC1)
(d) CH3NH2
(e) CH3OCH3
(f) N2H2 (HNNH)
(g) CH2CO
(h) HN3 (HNNN)
(i) N2O (NNO)
Q:The hydrocarbon propene (CH3-CH=CH2) can react in two different waysThe hydrocarbon propene (CH3-CH=CH2) can react in two different ways with bromine (Chapters 12 and 14).
(i)
The hydrocarbon propene (CH3-CH=CH2) can react in two different ways

(ii)

The hydrocarbon propene (CH3-CH=CH2) can react in two different ways

(a) Using the bond strengths (kcal mol-1) given in the margin, calculate △H° for each of these reactions, (b) △So ≈ 0 cal K-l mol-1 for one of these reactions and -35 cal K-l mol-1 for the other. Which reaction has which △So? Briefly explain your answer, (c) Calculate △G° for each reaction at 25°C and at 600°C. Are both of these reactions thermodynamically favorable at 25°C? At 600°C?

Q:(i) Determine whether each species in the following equations is(i) Determine whether each species in the following equations is acting as a Bronsted acid or base, and label it. (ii) Indicate whether the equilibrium lies to the left or to the right, (iii) Estimate K for each equation if possible.
(a) H2O + HCN ⇌ H3O+ + CN-
(b) CH3O- +NH3 ⇌ CH3OH + NH2-
(c) HF + CH3COO- ⇌ F- + CH3COOH
(d) CH3- + NH3 ⇌ CH4 + NH2-
(e) H3O+ + CI- ⇌ H2O + HCI
(f) CHCOOH + CH3S ⇌ CH3COO- + CH3SH
Q:Use curved arrows to show electron movement in each acid-baseUse curved arrows to show electron movement in each acid-base reaction in Problem 27.
Q:Identify each of the following species as either a LewisIdentify each of the following species as either a Lewis acid or a Lewis base, and write an equation illustrating a Lewis acid-base reaction for each one. Use curved arrows to depict electron-pair movement. Be sure that the product of each reaction is depicted by a complete, correct Lewis structure.
(a) CN-
(b) CH3OH
(c) (CH3)2CH+
(d) MgBr2
(e) CH3BH2
(f) CH3S-
Q:For each example in Table 2-3, identify all polarized covalentFor each example in Table 2-3, identify all polarized covalent bonds and label the appropriate atoms with partial positive or negative charges. (Do not consider carbon-hydrogen bonds.)
Q:Characterize each of the following atoms as being either nucleophilicCharacterize each of the following atoms as being either nucleophilic or electrophilic.
(a) Iodide ion, I-
(b) Hydrogen ion, H+
(c) Carbon in methyl cation, +CH3
(d) Sulfur in hydrogen sulfide. H2S
(e) Aluminum in aluminum trichloride. A1C13
(f) Magnesium in magnesium oxide, MgO
Q:Circle and identify by name each functional group in theCircle and identify by name each functional group in the compounds pictured.
(a)
Circle and identify by name each functional group in the

(b)

Circle and identify by name each functional group in the

(c)

Circle and identify by name each functional group in the

(d)

Circle and identify by name each functional group in the

(e)

Circle and identify by name each functional group in the

(f)

Circle and identify by name each functional group in the

(g)

Circle and identify by name each functional group in the

(h)

Circle and identify by name each functional group in the

(i)

Circle and identify by name each functional group in the

(j)

Circle and identify by name each functional group in theQ:On the basis of electrostatics (Coulomb attraction), predict which atomOn the basis of electrostatics (Coulomb attraction), predict which atom in each of the following organic molecules is likely to react with the indicated reagent. Write “no reaction” if none seems likely. (See Table 2-3 for the structures of the organic molecules.)
(a) Bromoethane. with the oxygen of HO-;
(b) Propanal, with the nitrogen of NH3
(c) Methoxyethane, with H+;
(d) 3-hexanone, with the carbon of CH3-
(e) Ethanenitrile (acetonitrile). with the carbon of CH3+;
(f) Butane, with HO-.
Q:Use curved arrows to show the electron movement in eachUse curved arrows to show the electron movement in each reaction in Problem 33.
Q:Name the following molecules according to the IUPAC system ofName the following molecules according to the IUPAC system of nomenclature.
(a)
Name the following molecules according to the IUPAC system of

(b)

Name the following molecules according to the IUPAC system of

(c)

Name the following molecules according to the IUPAC system of

(d)

Name the following molecules according to the IUPAC system of

(e) CH3CH(CH3)CH(CH3)CH(CH3)CH(CH3)2
(f)

Name the following molecules according to the IUPAC system ofName the following molecules according to the IUPAC system ofQ:Convert the following names into the corresponding molecular structures. AfterConvert the following names into the corresponding molecular structures. After doing so, check to see if the name of each molecule as given here is in accord with the IUPAC system of nomenclature. If not, name the molecule correctly, (a) 2-methyl-3-propylpentane; (b) 5-(l,l-dimethylpropyl)nonane; (c) 2,3,4-trimethyl-4-butylheptane; (d) 4-re/7-butyl-5-isopropylhexane; (e) 4-(2-ethylbutyl)decane; (f) 2,4,4-trimethylpentane; (g) 4-.vcc-butylheptane; (h) isoheptane; (i) neoheptane.
Q:Draw the structures that correspond to the following names. CorrectDraw the structures that correspond to the following names. Correct any names that are not in accord with the rules of systematic nomenclature.
(a) 4-Chloro-5-methylhexane
(b) 3-Methyl-3-propylpentane
(c) 1,1,1 -Trifluoro-2-methylpropane
(d) 4-(3-Bromobutyl)nonane
Q:Draw and name all possible isomers of C7HI6 (isomeric heptanes).Draw and name all possible isomers of C7HI6 (isomeric heptanes).
Q:Identify the primary, secondary, and tertiary carbon atoms and theIdentify the primary, secondary, and tertiary carbon atoms and the hydrogen atoms in each of the following molecules:
(a) Ethane;
(b) Pentane;
(c) 2-methylbutane;
(d) 3-ethyl-2,2,3,4-tetramethylpentane.
Q:Identify each of the following alkyl groups as being primary,Identify each of the following alkyl groups as being primary, secondary, or tertiary, and give it a systematic IUPAC name.
(a)
Identify each of the following alkyl groups as being primary,

(b)

Identify each of the following alkyl groups as being primary,

(c)

Identify each of the following alkyl groups as being primary,

(d)

Identify each of the following alkyl groups as being primary,

(e)

Identify each of the following alkyl groups as being primary,

(f)

Identify each of the following alkyl groups as being primary,Q:Rank the following molecules in order of increasing boiling pointRank the following molecules in order of increasing boiling point (without looking up the real values!):
(a) 3-methylheptane;
(b) Octane;
(c) 2,4-dimethylhexane;
(d) 2,2,4-trimethylpentane.
Q:Using Newman projections, draw each of the following molecules inUsing Newman projections, draw each of the following molecules in its most stable conformation with respect to the bond indicated:
(a) 2-methylbutane, C2-C3 bond;
(b) 2,2-dimethylbutane, C2-C3 bond;
(c) 2,2-dimethylpentane, C3-C4 bond;
(d) 2,2,4-trimethylpentane, C3-C4 bond.
Q:Based on the energy differences for the various conformations ofBased on the energy differences for the various conformations of ethane, propane, and butane in Figures 2-10, 2-11, and 2-13, determine the following:
(a) The energy associated with a single hydrogen-hydrogen eclipsing interaction
(b) The energy associated with a single methyl-hydrogen eclipsing interaction
(c) The energy associated with a single methyl-methyl eclipsing interaction
(d) The energy associated with a single methyl-methyl gauche interaction
Q:At room temperature, 2-methylbutane exists primarily as two alternating conformationsAt room temperature, 2-methylbutane exists primarily as two alternating conformations of rotation about the C2-C3 bond. About 90% of the molecules exist in the more favorable conformation and 10% in the less favorable one. (a) Calculate the free energy change (△G°, more favorable conformation – less favorable conformation) between these conformations, (b) Draw a potential-energy diagram for rotation about the C2-C3 bond in 2-methylbutane. To the best of your ability, assign relative energy values to all the conformations on your diagram, (c) Draw Newman projections for all staggered and eclipsed conformers in (b) and indicate the two most favorable ones.
Q:For each of the following naturally occurring compounds, identify theFor each of the following naturally occurring compounds, identify the compound class(es) to which it belongs, and circle all functional groups.
For each of the following naturally occurring compounds, identify theFor each of the following naturally occurring compounds, identify theQ:Give IUPAC names for all alkyl groups marked by dashedGive IUPAC names for all alkyl groups marked by dashed lines in each of the following biologically important compounds. Identify each group as a primary, secondary, or tertiary alkyl substituent.
Give IUPAC names for all alkyl groups marked by dashedQ:Using the Arrhenius equation, calculate the effect on k ofUsing the Arrhenius equation, calculate the effect on k of increases in temperature of 10, 30, and 50 degrees (Celsius) for the following activation energies. Use 300 K (approximately room temperature) as your initial T value, and assume that A is a constant, (a) Ea = 15 kcal mol-1 (b) Ea = 30 kcal mol-1; (c) Ea = 45 kcal mol-1.
Q:The Arrhenius equation can be reformulated in a way thatThe Arrhenius equation can be reformulated in a way that permits the experimental determination of activation energies. For this purpose, we take the natural logarithm of both sides and convert into the base 10 logarithm.
The Arrhenius equation can be reformulated in a way that

The rate constant k is measured at several temperatures T and a plot of log k versus 1 /T is prepared, a straight line. What is the slope of this line? What is its intercept (i.e., the value of log it at 1/T = 0)? How is E., calculated?

Q:Reexamine your answers to Problem 33. Rewrite each one inReexamine your answers to Problem 33. Rewrite each one in the form of a complete equation describing a Lewis acid-base process, showing the product and using curved arrows to depict electron-pair movement. [For (b) and (d), start with a Lewis structure that represents a second resonance form of the starting organic molecule.]
Q:The equation relating △Go to K contains a temperature term.The equation relating △Go to K contains a temperature term. Refer to your answer to Problem 44 (a) to calculate the answers to the questions that follow. You will need to know that △So for the formation of the more stable conformer of 2-methylbutane from the next most stable conformer is +1.4 cal K-l mol-1. (a) Calculate the enthalpy difference (△Ho) between these two conformers from the equation △Go = △H° – T△S°. How well does this agree with the △H° calculated from the number of gauche interactions in each conformer? (b) Assuming that △H° and △So do not change with temperature, calculate △G° between these two conformations at the following three temperatures: -250°C; – 100°C; +500°C. (c) Calculate K for these two conformations at the same three temperatures.
Q:Consider the difference in the rate between the following twoConsider the difference in the rate between the following two second-order substitution reactions.
Reaction 1: The reaction of bromoethane and iodide ion to produce iodoethane and bromide ion is second order: that is, the rate of the reaction depends on the concentrations of both bromoethane and iodide ion:
Rate = k[CH3CH2Br][I-] mol L-1 s-1
Reaction 2: The reaction of l-bromo-2,2-dimethylpropane (neopentyl bromide) with iodide ion to produce neopentyl iodide and bromide ion is more than 10,000 times slower than the reaction of bromoethane with iodide ion
Rate = k[neopentyl bromide][I-] mol L -1s-1
(a) Formulate each reaction by using bond-line structural drawings in your reaction scheme.
(b) Identify the reactive site of the starting haloalkane as primary, secondary, or tertiary.
(c) Discuss how the reaction might take place; that is, how the species would have to interact in order for the reaction to proceed. Remember that, because the reaction is second order, both reagents must be present in the transition state. Use your model kit to help you visualize the trajectory of approach of the iodide ion toward the bromoalkane that enables the simultaneous iodide bond making and bromide bond breaking required by the second-order kinetics of these two reactions. Of all the possibilities, which one best explains the experimentally determined difference in rate between the reactions?
(d) Use hashed-wedged line structures to make a three-dimensional drawing of the trajectory on which you agree.
Q:The compound 2-methylbutane has (a) No secondary H’s (b) No tertiary H’s (c)The compound 2-methylbutane has
(a) No secondary H’s
(b) No tertiary H’s
(c) No primary H’s
(d) Twice as many secondary H’s as tertiary H’s
(e) Twice as many primary H’s as secondary H’s
Q:The energy profile diagram represents (a) An endothermic reaction (b) An exothermicThe energy profile diagram represents
(a) An endothermic reaction
(b) An exothermic reaction
(c) A fast reaction
(d) A termolecular reaction
The energy profile diagram represents 
(a) An endothermic reaction 
(b) An exothermicQ:In 4-( l-methylethyl)heptane. any H-C-C angle has the value (a) 120° (b)In 4-( l-methylethyl)heptane. any H-C-C angle has the value
(a) 120°
(b) 109.5°
(c) 180°
(d) 90°
(e) 360°
Q:The structural representation shown in the margin is a NewmanThe structural representation shown in the margin is a Newman projection of the conformer of butane that is
(a) Gauche eclipsed
(b) Anti gauche
(c) Anti staggered
(d) Anti eclipsed
Q:Genipin (margin) is a Chinese herbal remedy that is effectiveGenipin (margin) is a Chinese herbal remedy that is effective against diabetes. To which of the compound classes below does genipin not belong?
(a) Alcohol
(b) Alkene
(c) Ester
(d) Ether
(e) Ketone
Q:Label the primary, secondary, and tertiary hydrogens in each ofLabel the primary, secondary, and tertiary hydrogens in each of the following compounds.
(a) CH3CH2CH2CH3
(b) CH3CH2CH2CH2CH3
(c)
Label the primary, secondary, and tertiary hydrogens in each of

(d)

Label the primary, secondary, and tertiary hydrogens in each ofQ:Within each of the following sets of alkyl radicals, nameWithin each of the following sets of alkyl radicals, name each radical; identify each as either primary, secondary, or tertiary; rank in order of decreasing stability; and sketch an orbital picture of the most stable radical, showing the hyperconjugative interaction(s).
(a)
Within each of the following sets of alkyl radicals, name

(b)

Within each of the following sets of alkyl radicals, name

(c)

Within each of the following sets of alkyl radicals, nameQ:Write as many products as you can think of thatWrite as many products as you can think of that might result from the pyrolytic cracking of propane. Assume that the only initial process is C-C bond cleavage.
Q:Answer the question posed in Problem 17 for (a) butaneAnswer the question posed in Problem 17 for (a) butane and (b) 2-methylpropane. Use the data in Table 3-2 to determine the bond most likely to cleave homolytically, and use that bond cleavage as your first step.
Problem 17
Write as many products as you can think of that might result from the pyrolytic cracking of propane. Assume that the only initial process is C-C bond cleavage.
Q:Calculate ∆Ho values for the following reactions. (a) H2 + F2Calculate ∆Ho values for the following reactions.
(a) H2 + F2 → 2 HF;
(b) H2 + Cl2 → 2 HC1;
(c) H2 + Br2 → 2 HBr;
(d) H2 + I2 → 2 HI;
(e) (CH3)3CH + F2 → (CH3)3CF + HF;
(f) (CH3)3CH + Cl2 → (CH3)3CCl + HC1;
(g) (CH3)3CH + Br2 → (CH3)3CBr + HBr;
(h) (CH3)3CH + I2 → (CH3)3CI + HI.
Q:For each compound in Problem 15, determine how many constitutionalFor each compound in Problem 15, determine how many constitutional isomers can form upon monohalogenation.
Problem 15
(a) CH3CH2CH2CH3
(b) CH3CH2CH2CH2CH3
(c)
For each compound in Problem 15, determine how many constitutional

(d)

For each compound in Problem 15, determine how many constitutionalQ:(a) Using the information given in Sections 3-6 and 3-7,(a) Using the information given in Sections 3-6 and 3-7, write the products of the radical monochlorination of
(i) Pentane and
(ii) 3-methylpentane.
(b) For each, estimate the ratio of the isomeric monochlorination products that would form at 25°C.
(c) Using the bond strength data from Table 3-1, determine the ∆H° values of the propagation steps for the chlorination of 3-methylpentane at C3. What is the overall ∆H° value for this reaction?
Q:Write in full the mechanism for monobromination of methane. BeWrite in full the mechanism for monobromination of methane. Be sure to include initiation, propagation, and termination steps.
Q:Sketch potential-energy/reaction-coordinate diagrams for the two propagation steps of theSketch potential-energy/reaction-coordinate diagrams for the two propagation steps of the mono-bromination of methane (Problem 22).
Q:Write a mechanism for the radical bromination of the hydrocarbonWrite a mechanism for the radical bromination of the hydrocarbon benzene, C6H6 (for structure, see Section 2-3). Use propagation steps similar to those in the halogenation of alkanes, as presented in Sections 3-4 through 3-6. Calculate ∆H° values for each step and for the reaction as a whole. How does this reaction compare thermodynamically with the bromination of other hydrocarbons? Data: DH° (C6H5-H) = 112 kcal mol-1; DH° (C6H5-Br) = 81 kcal mol-1. Note the Caution in Exercise 3-5.
Q:Sketch potential-energy/reaction-coordinate diagrams for the two propagation steps of theSketch potential-energy/reaction-coordinate diagrams for the two propagation steps of the mono-bromination of benzene (Problem 24).
Problem 24
Write a mechanism for the radical bromination of the hydrocarbon benzene, C6H6 (for structure, see Section 2-3). Use propagation steps similar to those in the halogenation of alkanes, as presented in Sections 3-4 through 3-6. Calculate ∆H° values for each step and for the reaction as a whole. How does this reaction compare thermodynamically with the bromination of other hydrocarbons? Data: DH° (C6H5-H) = 112 kcal mol-1; DH° (C6H5-Br) = 81 kcal mol-1. Note the Caution in Exercise 3-5.
Q:Identify each of the diagrams you drew in Problem 25Identify each of the diagrams you drew in Problem 25 as showing an early or a late transition state.
Q:Write the major organic product(s), if any, of each ofWrite the major organic product(s), if any, of each of the following reactions.
(a)
Write the major organic product(s), if any, of each of

(b)

Write the major organic product(s), if any, of each of

(c)

Write the major organic product(s), if any, of each of

(d)

Write the major organic product(s), if any, of each of

(e)

Write the major organic product(s), if any, of each ofQ:Calculate product ratios in each of the reactions in ProblemCalculate product ratios in each of the reactions in Problem 27. Use relative reactivity data for F2 and Cl2 at 25°C and for Br2 at 150°C (Table 3-6).
Problem 27
(a)
Calculate product ratios in each of the reactions in Problem

(b)

Calculate product ratios in each of the reactions in Problem

(c)

Calculate product ratios in each of the reactions in Problem

(d)

Calculate product ratios in each of the reactions in Problem

(e)

Calculate product ratios in each of the reactions in ProblemQ:Which, if any, of the reactions in Problem 27 giveWhich, if any, of the reactions in Problem 27 give the major product with reasonable selectivity (i.e., are useful “synthetic methods”)?
Problem 27
(a)
Which, if any, of the reactions in Problem 27 give

(b)

Which, if any, of the reactions in Problem 27 give

(c)

Which, if any, of the reactions in Problem 27 give

(d)

Which, if any, of the reactions in Problem 27 give

(e)

Which, if any, of the reactions in Problem 27 giveQ:(a) What would be the major organic product of monobromination(a) What would be the major organic product of monobromination of pentane at I25°C?
(b) Draw Newman projections of all possible staggered conformations arising from rotation about the C2-C3 bond for this product molecule.
(c) Draw a qualitative graph of potential energj versus torsional angle for C2-C3 rotation in this molecule.

Q:(a) Sketch a potential energy/reaction coordinate graph showing the two(a) Sketch a potential energy/reaction coordinate graph showing the two propagation steps for the monobromination of pentane to give the major product (Problem 30). Use DH° information from this chapter (Tables 3-1, 3-2, and 3-4, as appropriate).
(b) Indicate the locations of the transition states and whether each is early or late.
(c) Sketch a similar graph for reaction of pentane with I2. How does it differ from the graph for bromination?
Q:At room temperature, 1,2-dibromoethane exists as an equilibrium mixture inAt room temperature, 1,2-dibromoethane exists as an equilibrium mixture in which 89% of the molecules are in an anti conformation and 11% are gauche. The comparable ratio for butane under the same circumstances is 72% anti and 28% gauche. Suggest an explanation for the difference, bearing in mind that Br is sterically smaller than CH3.
Q:Sulfuryl chloride (SO2Cl2, see structure) is a liquid reagent thatSulfuryl chloride (SO2Cl2, see structure) is a liquid reagent that may be used for chlorinations of alkanes as a substitute for gaseous elemental chlorine. Propose a mechanism for chlorination of CH4 using sulfuryl chloride.
Sulfuryl chloride (SO2Cl2, see structure) is a liquid reagent thatQ:Use the Arrhenius equation (Section 2-1) to estimate the ratioUse the Arrhenius equation (Section 2-1) to estimate the ratio of the rate constants k for the reactions of a C-H bond in methane with a chlorine atom and with a bromine atom at 25°C. Assume that the A values for the two processes are equal, and use Ea = 19 kcal mol-1 for the reaction between Br∙ and CH4.
Q:When an alkane with different types of C-H bonds, suchWhen an alkane with different types of C-H bonds, such as propane, reacts with an equimolar mixture of Br2 and Cl2, the selectivity in the formation of the brominated products is much worse than that observed when reaction is carried out with Br2 alone. (In fact, it is very similar to the selectivity for chlorination.) Explain.
Q:Bromination of 1-bromopropane gives the following results: Calculate the relative reactivitiesBromination of 1-bromopropane gives the following results:
Bromination of 1-bromopropane gives the following results: 
Calculate the relative reactivities

Calculate the relative reactivities of the hydrogens on each of the three carbons toward bromine atoms. Compare these results with those from a simple alkane such as propane, and suggest explanations for any differences.

Q:A hypothetical alternative mechanism for the halogenation of methane hasA hypothetical alternative mechanism for the halogenation of methane has the following propagation steps.
(i) X∙ + CH4 → CH3X + H∙
(ii) H∙ + X2 → HX + X∙
(a) Using DH° values from appropriate tables, calculate ∆H° for these steps for any one of the halogens.
(b) Compare your ∆H° values with those for the accepted mechanism (Table 3-5). Do you expect this alternative mechanism to compete successfully with the accepted one?
Q:The addition of certain materials called radical inhibitors to halogenationThe addition of certain materials called radical inhibitors to halogenation reactions

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