Calculate the dihedral angle (θ) for the conformations shown.

(a)

Calculate the dihedral angle (θ) for the conformations shown.

(c)

Why is it incorrect to say that the dihedral angle shown is 120° or even 109°?

Calculate the total strain in the eclipsed conformations shown.

(a)

Calculate the total strain in the eclipsed conformations shown.

(b)

Would you expect a CH₃/CH₃ eclipsing interaction to be larger or smaller than 1.3 kcal/mol?

Choose the conformation in each pair that is most stable. If both are equally stable, then write 'no difference.'

(a)

For each of the pairs in Assessment 3.29, which conformation would you expect to be more prominent at equilibrium?

(a)

(b)

(c)

Name the following cycloalkanes using the IUPAC system of nomenclature. [Hint: Each molecule exemplifies one of the cycloalkane nomenclature rules in Table 3.10.]

(a) rule 1

Name the following cycloalkanes using the IUPAC system of nomenclature. [Hint: Each molecule exemplifies one of the cycloalkane nomenclature rules in Table 3.10.]

(c) rule 2

Name the following cycloalkanes using the IUPAC system of nomenclature. [Hint: Each molecule exemplifies one of the cycloalkane nomenclature rules in Table 3.10.]

(e) rule 3

Name the following cycloalkanes using the IUPAC system of nomenclature. [Hint: Each molecule exemplifies one of the cycloalkane nomenclature rules in Table 3.10.]

(g) rule 4

Name the following cycloalkanes using the IUPAC system of nomenclature.

Name the following cycloalkanes using the IUPAC system of nomenclature, being sure to indicate whether they are cis or trans.

(b)

Rank the following compounds in order of their total heat of combustion. These compounds are constitutional isomers, each with a molecular formula of C₆H₁₂.

Draw two chair conformations of the molecules below. Indicate which is most stable.

(a)

Given the following chair conformations, draw each in its planar form as if you were viewing it from above.

(b)

Given the following chair conformations, draw each in its planar form as if you were viewing it from above.

(c)

Given the following chair conformations, draw each in its planar form as if you were viewing it from above.

(d)

Draw two different chair conformations for each of the following molecules. Make sure that your drawings clearly show the cis–trans stereochemistry.

(c)

For each pair of conformations you drew in Assessment 3.41, indicate which is most stable.

Draw the most stable chair conformation for the following trisubstituted cyclohexane.

Based on the formal charge, determine how many lone pairs are on each indicated atom.

(a)

Modify the following line-angle drawings to show all lone pairs.

(a)

Modify the following line-angle drawings to show all lone pairs.

(b)

Given the line-angle drawings shown, answer the following questions:

(i) How many carbons are in each molecule?

(ii) How many hydrogens are at the circled carbon?

(iii) Is the indicated (→) carbon or 1° , 2°, 3°, or 4°?

(c)

Given the line-angle drawings shown, answer the following questions:

(i) How many carbons are in each molecule?

(ii) How many hydrogens are at the circled carbon?

(iii) Is the indicated (→) carbon or 1° , 2°, 3°, or 4°?

(e)

Given the line-angle drawings shown, answer the following questions:

(i) How many carbons are in each molecule?

(ii) How many hydrogens are at the circled carbon?

(iii) Is the indicated (→) carbon or 1° , 2°, 3°, or 4°?

(f)

Given the line-angle drawings shown, answer the following questions:

(i) How many carbons are in each molecule?

(ii) How many hydrogens are at the circled carbon?

(iii) Is the indicated (→) carbon or 1° , 2°, 3°, or 4°?

(h)

Represent each of the following condensed structural formulas using a line-angle drawing.

(c) CH₃CHOHCH₂CHBrCH₃