a. Which is the most stable: 3,4-dimethyl-2-hexene, 2,3-dimethyl-2-hexene, or 4,5-dimethyl-2-hexene?

b. Which compound has the largest heat of hydrogenation?

c. Which compound has the smallest heat of hydrogenation?

Draw the skeletal structure of 3,3-dimethyl-7-(1-methylethyl)-6-(1-methylpropyl)decane.

In a reaction in which reactant A is in equilibrium with product B at 25 °C, what relative amounts of A and B are present at equilibrium if ∆G° at 25 °C is

a. 2.72 kcal/mol?

b. 0.65 kcal/mol?

In a reaction in which reactant A is in equilibrium with product B at 25 °C, what relative amounts of A and B are present at equilibrium if ∆G° at 25 °C is

c. -2.72 kcal/mol?

d. -0.65 kcal/mol?

Which bond is stronger? Briefly explain why.

a.

Which bond is stronger? Briefly explain why.

b.

For each of the following compounds, draw the possible geometric isomers and name each isomer:

a. 2-methyl-2,4-hexadiene

For each of the following compounds, draw the possible geometric isomers and name each isomer:

b. 1,5-heptadiene

For each of the following compounds, draw the possible geometric isomers and name each isomer:

c. 1,4-pentadiene

For each of the following compounds, draw the possible geometric isomers and name each isomer:

d. 3-methyl-2,4-hexadiene

How many of the following names are correct? Correct the incorrect names.

a. 3-pentene

b. 2-octene

c. 2-vinylpentane

How many of the following names are correct? Correct the incorrect names.

d. 1-ethyl-1-pentene

e. 5-ethylcyclohexene

f. 5-chloro-3-hexene

How many of the following names are correct? Correct the incorrect names.

g. 2-ethyl-2-butene

h. (E)-2-methyl-1-hexene

i. 2-methylcyclopentene

a. How many alkenes could you treat with H₂, Pd/C to prepare methylcyclopentane?

b. Which of the alkenes is the most stable?

c. Which of the alkenes has the smallest heat of hydrogenation?

Draw structures for the following:

c. (3Z,5Z)-4,5-dimethyl-3,5-nonadiene

d. (3E,5E)-2,5-dibromo-3,5-octadiene

Given the reaction coordinate diagram for the reaction of A to form G, answer the following questions:

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a. How many intermediates are formed in the reaction?

b. Which letters represent transition states?

c. What is the fastest step in the reaction?

d. Which is more stable: A or G?

e. Does A or E form faster from C?

f. Which is the more stable intermediate?

a. Which of the following reactions has the larger ∆S° value?

b. Is the ∆S° value positive or negative?

Draw the structure of a compound with molecular C₈H₁₄ that reacts with one equivalent of H₂ over Pd/C to form a meso compound

a. What is the equilibrium constant for a reaction that is carried out at 25 °C (298 K) with ∆H° = 20 kcal/mol and ∆S° = 5.0 × 10^-2 kcal mol^-1 K^-1?

b. What is the equilibrium constant for the same reaction carried out at 125 °C?

Using curved arrows, show the mechanism of the following reaction:

For a reaction carried out at 25 °C with an equilibrium constant of 1 × 10^-3, to increase the equilibrium constant by a factor of 10:

a. how much must ∆G° change?

b. how much must ∆H° change if ∆S° = 0 kcal mol^-1 K^-1?

c. how much must ∆S° change if ∆H° = 0 kcal mol^-1?

Given that the free energy of the twist-boat conformer of cyclohexane is 5.3 kcal/mol greater than that of the chair conformer, calculate the percentage of twist-boat conformers present in a sample of cyclohexane at 25 °C. Does your answer agree with the statement made in Section 3.13 about the relative number of molecules in these two conformations?

From the following rate constants, determined at five temperatures, calculate the experimental energy of activation and ∆G^‡, ∆H^‡, and ∆S^‡ for the reaction at 30 °C:

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