Question 1

Which of the following best explains why fish develop a 'fishy' odor as they spoil?

Accepted Answer

The reduction of trimethylamine oxide (TMAO) to trimethylamine, which is volatile and has a strong odor.

Question 2

Which of the following compounds is a secondary amine?

Accepted Answer

Piperidine

Question 3

What is the IUPAC name for the following structure: $$\mathrm{CH_3CH_2NH_2}$$?

Accepted Answer

Ethanamine

Question 4

Which of the following statements about the basicity of amines is correct?

Accepted Answer

Alkyl groups increase the basicity of amines by stabilizing the ammonium ion formed upon protonation.

Question 5

Which of the following amines is the least basic?

Accepted Answer

Pyrrole

Question 6

What is the major product when a tertiary amine is oxidized with hydrogen peroxide ($$\mathrm{H_2O_2}$$)?

Accepted Answer

An amine oxide

Question 7

Which of the following best describes the hybridization and geometry of the nitrogen atom in a simple amine such as methylamine?

Accepted Answer

sp$$^3$$ hybridized, tetrahedral geometry with a bond angle slightly less than $$109.5^\circ$$

Question 8

Which of the following statements about the boiling points of amines is correct?

Accepted Answer

Primary and secondary amines have higher boiling points than tertiary amines due to hydrogen bonding.

Question 9

Which of the following is the correct equation for the base dissociation constant ($$K_b) of a $$primary amine in water?

Accepted Answer

$$K_b = \frac{[\mathrm{$$RNH_3$$^+}][\mathrm{OH^-}]}{[\mathrm{$$RNH_2$$}]}$$

Question 10

Which of the following best explains why aniline is less basic than ethylamine?

Accepted Answer

The lone pair on the nitrogen in aniline is delocalized into the aromatic ring, reducing its availability for protonation.

Question 11

Which of the following is a correct statement about the separation of amines from a mixture using acid-base extraction?

Accepted Answer

Amines are converted to water-soluble ammonium salts by treatment with aqueous acid.

Question 12

Which of the following is the major product when butan-1-amine is treated with excess methyl iodide and sodium bicarbonate?

Accepted Answer

$$\mathrm{CH_3CH_2CH_2CH_2N^+(CH_3$)_3\ I^-}$$

Question 13

Which of the following best describes the outcome of the Hofmann elimination reaction?

Accepted Answer

The least substituted alkene is formed as the major product.

Question 14

Which of the following is a correct statement about the Gabriel synthesis?

Accepted Answer

It is used to prepare primary amines via nucleophilic substitution with phthalimide.

Question 15

Which of the following is the correct IR absorption range for the N–H stretch in a primary amine?

Accepted Answer

$$3200\ 	ext{to}\ 3500\ 	ext{cm}^{-1}$$

Question 16

Which of the following statements about the mass spectrometry of amines is correct?

Accepted Answer

A molecular ion with an odd mass number indicates an odd number of nitrogen atoms.

Question 17

Which of the following is the correct product when a primary amine reacts with an acid chloride?

Accepted Answer

An amide

Question 18

Which of the following best explains why tertiary amines are less soluble in water than primary or secondary amines?

Accepted Answer

Tertiary amines cannot form hydrogen bonds with water as donors.

Chapter 19: Amines – Structure, Properties, and Reactions

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