Question 1

Arrange the following amines in order of decreasing water solubility, putting the most soluble amine first.  &#10;A)I > II > III&#10;B)II > I > III&#10;C)III > I > II&#10;D)II > III > I

Accepted Answer

Amines with hydrogen bonding capability tend to be more soluble in water due to the ability to form hydrogen bonds with water molecules. In this case, amine II has two amine groups with the potential to form hydrogen bonds, while amine I only has one amine group, and amine III has no amine groups for hydrogen bonding. Therefore, amine II will be the most soluble, followed by amine I, and then amine III.

Question 2

What is the common name of the following compound?&#10; &#10;A)diisopropylamine&#10;B)dipropylamine&#10;C)diisopropanamine&#10;D)dibutylamine

Accepted Answer

diisopropylamine

Question 3

What is the common name of the following compound?&#10; &#10;A)dimethylisobutylamine&#10;B)butyldimethylamine&#10;C)N,N-dimethylbutanamine&#10;D)sec-butyldimethylamine

Accepted Answer

The compound contains a sec-butyl group, which means the butyl group is attached to the second carbon of the parent chain. Therefore, the name should include the prefix "sec-". Additionally, there are two methyl groups attached to the nitrogen atom, which gives the suffix "-dimethylamine". Therefore, the correct name is sec-butyldimethylamine.

Question 4

Although an amine nitrogen atom containing an electron pair and bonded to three different groups is technically a stereogenic center, the chirality of the amine nitrogen is often ignored.Why is that? A)Because four bonds are needed to define a stereogenic center. B)Because chirality only exists with the tetrahedral carbon atoms. C)Because there is usually slow interconversion between the two isomeric forms at room temperature. D)Because there is usually rapid interconversion between the two isomeric forms at room temperature.

Accepted Answer

Because there is usually rapid interconversion between the two isomeric forms at room temperature, the chirality of the amine nitrogen is often ignored as the two forms cannot be isolated.

Question 5

What is the IUPAC name of the following compound?&#10; &#10;A)3-methyl-1-hexanamine&#10;B)4-methyl-1-hexylamine&#10;C)4-methyl-1-hexanamine&#10;D)3-methyl-6-hexylamine

Accepted Answer

The longest carbon chain has 6 carbon atoms, so the parent chain is hexane. The substituent on the fourth carbon atom is a methyl group (-CH3), and the functional group is an amine (-NH2). Since the methyl substituent is on the fourth carbon, it is 4-methyl-hexan-amine. However, since the amine group is a higher priority functional group than the methyl substituent, we number the carbon chain so that the amine group has the lowest possible number. Therefore, the correct IUPAC name is 4-methyl-1-hexanamine.

Question 6

Arrange the following compounds in order of increasing boiling point, putting the compound with the least boiling point first. A)I < II < III B)II < I < III C)I < III < II D)II < III < I

Accepted Answer

The answer of Arrange the following compounds in order...

Question 7

The mass spectrum of an amine shows a parent peak with an odd mass for the molecular ion.What does this tell you about the amine? A)The amine is a primary amine. B)The amine is a secondary amine. C)The amine contains an even number of N atoms. D)The amine contains an odd number of N atoms.

Accepted Answer

An odd mass for the molecular ion suggests the presence of an odd number of nitrogen atoms. Therefore, the correct answer is (D) the amine contains an odd number of N atoms.

Question 8

What is the IUPAC name of the following compound?&#10; &#10;A)N-ethyl-N-methylpentylamine&#10;B)N-ethyl-N-methyl-1-pentanamine&#10;C)N-methyl-3-octanamine&#10;D)N-ethyl-2-heptanamine

Accepted Answer

The longest carbon chain contains 6 carbons, making it a pentane. The amine group is located on the first carbon and has one methyl substituent and one ethyl substituent. Therefore, the correct name is N-ethyl-N-methyl-1-pentanamine.

Question 9

Arrange the following compounds in order of decreasing boiling point, putting the compound with the highest boiling point first. A)I > II > III B)I > III > II C)III > I > II D)III > II > I

Accepted Answer

The boiling point of a compound is primarily determined by two factors: the strength of the intermolecular forces and the size of the molecule. In this case, all three compounds are polar and can form hydrogen bonds, which are the strongest intermolecular forces. However, as the size of the molecule increases, the boiling point also increases because there are more electrons that can participate in London dispersion forces.

Compound I is the smallest and has the fewest electrons, so it has the weakest London dispersion forces. Compound II is larger than I and has more electrons, so it has stronger London dispersion forces. Compound III is the largest and has the most electrons, so it has the strongest London dispersion forces.

Therefore, the correct order of decreasing boiling points is III > I > II, which corresponds to choice C.

Question 10

What is the correct assignment of the names of the following aromatic amines?&#10; &#10;A)I = pyrrolidine; II = pyrimidine; III = aniline.&#10;B)I = pyrrole; II = pyrimidine; III = anisole.&#10;C)I = pyrrolidine; II = pyridine; III =aniline.&#10;D)I = pyrrole; II = pyridine; III = aniline.

Accepted Answer

I is a pyrrole because it has a five-membered ring with four carbons and a nitrogen. 
II is a pyridine because it has a six-membered ring with five carbons and a nitrogen in the ring. 
III is an aniline because it has a benzene ring with an amino group (-NH2) attached to it.

Question 11

What is the approximate bond angle of the substituents around a nitrogen atom in amines?&#10;A)90&#176;&#10;B)109.5&#176;&#10;C)120&#176;&#10;D)180&#176;

Accepted Answer

The answer of What is the approximate bond angle of...

Question 12

Which of the following amines are classified as primary (1&#176;) amines?&#10; &#10;A)I&#10;B)II&#10;C)III&#10;D)I and II

Accepted Answer

The answer of Which of the following amines are classified...

Question 13

Why should the chirality of an ammonium salt with four different groups on the nitrogen atom not be ignored?&#10;A)Because there is rapid interconversion between the two isomeric forms at room temperature.&#10;B)Because interconversion cannot occur between the two isomeric forms at room temperature.&#10;C)Because the compound would be a meso compound.&#10;D)Because the compound would be a racemic mixture.

Accepted Answer

The answer of Why should the chirality of an ammonium...

Question 14

What is the IUPAC name of the following compound?&#10; &#10;A)(Z)-4-hexen-1-amine&#10;B)(E)-4-hexen-1-amine&#10;C)(E)-2-hexen-6-amine&#10;D)(Z)-2-hexen-6-amine

Accepted Answer