Q: Which of the following best describes the gauche interaction in a Newman projection of butane?

Two methyl groups are 60° apart.

Q: Which of the following is the correct calculation for the degree of unsaturation for a molecule with formula $C\_7H\_{12}$?

$\frac{2C+2-H}{2} = \frac{2\times7+2-12}{2} = 2$

Q: Which of the following best explains why 1,3-diaxial interactions increase the energy of cyclohexane chair conformations?

They are repulsive steric interactions between axial substituents and axial hydrogens.

Q: Which of the following statements about torsional strain is correct?

It is minimized in the staggered conformation.

Q: Which of the following is the correct structure for ethylcyclohexane?

Cyclohexane ring with an ethyl group attached

Q: Which of the following best describes the effect of increasing the number of carbons in an alkane on its boiling point?

Boiling point increases due to stronger London dispersion forces.

Question 1

Which of the following molecules contains both an alcohol and a ketone functional group?

Accepted Answer

CH\_3COCH\_2OH

Question 2

Given the molecular formula C\_5H\_{12}, which of the following is a possible structure for a saturated hydrocarbon (alkane)?

Accepted Answer

2-methylbutane

Question 3

Which abbreviation is commonly used for a methyl group in organic chemistry skeletal structures?

Accepted Answer

Me

Question 4

Which of the following correctly describes the difference between a chair and a boat conformation of cyclohexane?

Accepted Answer

Chair conformation is more stable due to minimized torsional and steric strain.

Question 5

Which of the following is the correct Newman projection for the most stable conformation of ethane?

Accepted Answer

Staggered

Question 6

When ranking the boiling points of the following compounds, which intermolecular force is most significant for ethanol (CH\_3CH\_2OH)?

Accepted Answer

Hydrogen bonding

Question 7

Which of the following statements about cyclohexane is TRUE?

Accepted Answer

Equatorial positions minimize 1,3-diaxial interactions, increasing stability.

Question 8

A molecule has the formula C\_4H\_{10}. Which of the following is NOT a possible isomer?

Accepted Answer

cyclobutane

Question 9

Which of the following best explains why tert-butyl carbons are classified as tertiary?

Accepted Answer

They are bonded to three other carbon atoms.

Question 10

Which of the following solvents would best dissolve a nonpolar alkane?

Accepted Answer

Hexane

Question 11

Which of the following is the correct formula for a cycloalkane with 6 carbon atoms?

Accepted Answer

$C\_6H\_{12}$

Question 12

Which of the following is the correct order of increasing boiling point for the following compounds: methane, ethane, propane?

Accepted Answer

Methane < Ethane < Propane

Question 13

Which of the following best describes the gauche interaction in a Newman projection of butane?

Accepted Answer

Two methyl groups are 60° apart.

Question 14

Which of the following is the correct calculation for the degree of unsaturation for a molecule with formula $C\_7H\_{12}$?

Accepted Answer

$\frac{2C+2-H}{2} = \frac{2	imes7+2-12}{2} = 2$

Question 15

Which of the following best explains why 1,3-diaxial interactions increase the energy of cyclohexane chair conformations?

Accepted Answer

They are repulsive steric interactions between axial substituents and axial hydrogens.

Question 16

Which of the following is the correct IUPAC name for the compound with the structure $CH\_3CH\_2CH(CH\_3)CH\_3$?

Accepted Answer

2-methylbutane

Question 17

Which of the following statements about torsional strain is correct?

Accepted Answer

It is minimized in the staggered conformation.

Question 18

Which of the following is the correct structure for ethylcyclohexane?

Accepted Answer

Cyclohexane ring with an ethyl group attached

Question 19

Which of the following best describes the effect of increasing the number of carbons in an alkane on its boiling point?

Accepted Answer

Boiling point increases due to stronger London dispersion forces.

Question 20

Which of the following is the correct formula for a saturated hydrocarbon with 8 carbon atoms?

Accepted Answer

$C\_8H\_{18}$

Organic Chemistry Study Guide: Chapters 3 & 4 Key Concepts

Study Guide - Practice Questions

Study Guide - Flashcards