All of the following names are incorrect or incomplete. In each case, draw the structure (or a possible structure) and name it correctly.

a. 3-ethyl-4-methylpentane

b. 2-ethyl-3-methylpentane

c. 3-dimethylhexane

All of the following names are incorrect or incomplete. In each case, draw the structure (or a possible structure) and name it correctly.

d. 4-isobutylheptane

e. 2-bromo-3-ethylbutane

f. 2,3-diethyl-5-isopropylheptane

Give structures and names for

a. the five isomers of C₆H₁₄

Draw the structures of the following groups, and give their more common names.

a. the (1-methylethyl) group

b. the (2-methylpropyl) group

c. the (1-methylpropyl) group

d. the (1,1-dimethylethyl) group

e. the (3-methylbutyl) group, sometimes called the 'isoamyl' group

Draw the structures of the following compounds.

a. 4-(1,1-dimethylethyl)octane

Draw the structures of the following compounds.

b. 5-(1,2,2-trimethylpropyl)nonane

Draw the structures of the following compounds.

c. 3,3-diethyl-4-(2,2-dimethylpropyl)octane

Without looking at the structures, give molecular formulas for the compounds: (a) 4-(1,1-dimethylethyl)octane and (b) 5-(1,2,2-trimethylpropyl)nonane. Use the names of the groups to determine the number of carbon atoms; then use the (2n + 2) rule.

List each set of compounds in order of increasing boiling point.

a. hexane, octane, and decane

List each set of compounds in order of increasing boiling point.

b. Octane, (CH₃)₃C—C(CH₃)₃ and CH₃CH₂C(CH₃)₂CH₂CH₂CH₃

Draw Newman projections of the following molecules viewed from the direction of the blue arrows.

(a)

Draw Newman projections of the following molecules viewed from the direction of the blue arrows.

(b)

Draw Newman projections of the following molecules viewed from the direction of the blue arrows.

(c)

Draw a graph, similar to Figure 3-9, of the torsional strain of 2-methylpropane as it rotates about the bond between C1 and C2. Show the dihedral angle and draw a Newman projection for each staggered and eclipsed conformation.

Draw a graph, similar to Figure 3-11, of the torsional energy of 2-methylbutane as it rotates about the C2—C3 bond.

Draw a perspective representation of the most stable conformation of 3-methylhexane.

Give IUPAC names for the following compounds.

Draw the structure and give the molecular formula for each of the following compounds.

a. 1-ethyl-3-methylcycloheptane

b. isobutylcyclohexane

Draw the structure and give the molecular formula for each of the following compounds.

c. cyclopropylcyclopentane

d. 3-ethyl-1,1-dimethylcyclohexane

Draw the structure and give the molecular formula for each of the following compounds.

e. 3-ethyl-2,4-dimethylhexane

f. 1,1-diethyl-4-(3,3-dimethylbutyl)cyclohexane

Draw the structure that corresponds with each name.

k. cyclobutylcyclohexane

l. cis-1-bromo-3-chlorocyclohexane

Which of the following cycloalkanes are capable of geometric (cis-trans) isomerism? Draw the cis and trans isomers.

a. 3-ethyl-1,1-dimethylcyclohexane

Which of the following cycloalkanes are capable of geometric (cis-trans) isomerism? Draw the cis and trans isomers.

b. 1-ethyl-3-methylcycloheptane

Which of the following cycloalkanes are capable of geometric (cis-trans) isomerism? Draw the cis and trans isomers.

c. 1-ethyl-3-methylcyclopentane

The heat of combustion of cis-1,2-dimethylcyclopropane is larger than that of the trans isomer. Which isomer is more stable? Use drawings to explain this difference in stability.

trans-1,2-Dimethylcyclobutane is more stable than cis-1,2-dimethylcyclobutane, but cis-1,3-dimethylcyclobutane is more stable than trans-1,3-dimethylcyclobutane. Use drawings to explain these observations.

The cyclohexane chair shown in Figure 3-22 has the headrest to the right and the footrest to the left. Draw a cyclohexane chair with its axial and equatorial bonds, showing the headrest to the left and the footrest to the right.

Draw 1,2,3,4,5,6-hexamethylcyclohexane with all the methyl groups

a. in axial positions.

Draw 1,2,3,4,5,6-hexamethylcyclohexane with all the methyl groups

b. in equatorial positions.

Draw a Newman projection, similar to Figure 3-25 down the C1—C6 bond in the ­equatorial conformation of methylcyclohexane. Show that the equatorial methyl group is also anti to C5. (Using your models will help.)

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