Question 1

Which of the following best describes the functional groups present in 1,5-dihydroxy-4-methyl-2-pentanone?

Accepted Answer

Two hydroxyl groups and one ketone group

Question 2

Which of the following is the correct common name for the molecule with the structure $$\mathrm{CH_3COCH_2CH_3}$$?

Accepted Answer

Ethyl methyl ketone

Question 3

A compound undergoes catalytic hydrogenation with $$\mathrm{H_2$}$$ and Pt. If the starting compound is 4-methyl-2-pentanone, what is the major organic product?

Accepted Answer

4-methyl-2-pentanol

Question 4

Which of the following best describes a hemiacetal functional group?

Accepted Answer

A carbon bonded to one -OH group, one -OR group, one hydrogen, and one alkyl group

Question 5

Which of the following Fischer projections represents an aldose?

Accepted Answer

A monosaccharide with an aldehyde group at the top carbon

Question 6

Which of the following compounds can exist as a pair of enantiomers (mirror-image twins)?

Accepted Answer

A molecule with at least one chiral center and no plane of symmetry

Question 7

Two monosaccharides are shown as Fischer projections. If all chiral centers are opposite in configuration, what is the relationship between the two molecules?

Accepted Answer

They are enantiomers

Question 8

Which of the following best describes the Haworth projection of D-glucose in its most common cyclic form?

Accepted Answer

A six-membered ring (pyranose) with the anomeric -OH group down for the alpha form

Question 9

Which Fischer projection would produce L-threitol upon reduction?

Accepted Answer

A four-carbon aldose with the -OH groups on the left at C2 and right at C3

Question 10

What is the systematic name for the molecule with the structure $$\mathrm{CH_3CH(OH)CH_2CH_2CHO}$$?

Accepted Answer

4-hydroxy-pentanal

Question 11

A disaccharide contains a glycosidic bond between the anomeric carbon of one glucose and the C4 of another glucose. Which of the following best describes this bond?

Accepted Answer

$$\alpha-1$$,4-glycosidic bond

Question 12

Which of the following statements is true about reducing sugars?

Accepted Answer

They contain a free anomeric carbon that can act as a reducing agent

Question 13

Which of the following is an L-aldopentose?

Accepted Answer

A five-carbon aldose with the -OH group on the left at the highest-numbered chiral center

Question 14

Which of the following best describes the product of the reduction of D-erythrose?

Accepted Answer

D-erythritol

Question 15

Which of the following statements about acetal formation is correct?

Accepted Answer

Acetals are formed when a hemiacetal reacts with an alcohol under acidic conditions

Question 16

Which of the following best describes the difference between D- and L- monosaccharides?

Accepted Answer

The configuration of the chiral center farthest from the carbonyl group

Question 17

Which of the following is true about the hydrolysis of a disaccharide with an $$\alpha-1$$,4-glycosidic bond?

Accepted Answer

It produces two monosaccharides, one of which has a free anomeric carbon

Question 18

Which of the following best describes the structure of a ketose?

Accepted Answer

A monosaccharide with a ketone group at the second carbon

Question 19

Which of the following is a correct statement about mirror-image isomers (enantiomers) of monosaccharides?

Accepted Answer

They have identical physical properties except for the direction in which they rotate plane-polarized light

Question 20

Which of the following best describes the relationship between glucose and galactose?

Accepted Answer

They are diastereomers

CHEM 105 GOB Practice Exam 2 (Ch. 14 & 15) – Step-by-Step Study Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard