Question 1

Which of the following best describes the molecular formula of a carbohydrate?

Accepted Answer

$$\mathrm{C}_n(\mathrm{H}_2\mathrm{O})_n$$

Question 2

Which of the following statements about D- and L- sugars is correct?

Accepted Answer

D- and L- refer to the configuration relative to D- and L-glyceraldehyde.

Question 3

Which of the following is the smallest aldose?

Accepted Answer

Glyceraldehyde

Question 4

Which of the following best describes an epimer?

Accepted Answer

A stereoisomer that differs at only one asymmetric center

Question 5

Which reagent will oxidize an aldose to an aldonic acid but not affect a ketose?

Accepted Answer

$$\mathrm{Br}_2$$

Question 6

What is the product when D-glucose is treated with excess $$\mathrm{HNO}_3$$?

Accepted Answer

D-glucaric acid

Question 7

Which of the following statements about the Kiliani–Fischer synthesis is correct?

Accepted Answer

It increases the carbon chain of an aldose by one carbon and produces a pair of C-2 epimers.

Question 8

Which of the following is a reducing sugar?

Accepted Answer

Maltose

Question 9

Which of the following best explains why sucrose is a nonreducing sugar?

Accepted Answer

Both anomeric carbons are involved in the glycosidic bond.

Question 10

Which of the following is true about the anomeric effect?

Accepted Answer

It is the preference for the axial position at the anomeric carbon for certain substituents.

Question 11

Which of the following is the main structural difference between D-glucose and D-fructose?

Accepted Answer

D-glucose is a polyhydroxy aldehyde, D-fructose is a polyhydroxy ketone.

Question 12

Which of the following best describes the difference between alpha-D-glucose and beta-D-glucose?

Accepted Answer

They differ in the configuration at the C-1 (anomeric) carbon.

Question 13

Which of the following is a correct statement about the stability of glucose anomers?

Accepted Answer

Beta-D-glucose is more stable than alpha-D-glucose.

Question 14

Which of the following is a C-4 epimer of D-glucose?

Accepted Answer

D-galactose

Question 15

Which of the following best describes the result of hydrolyzing a polysaccharide?

Accepted Answer

Formation of monosaccharides

Question 16

Which of the following is true about the Wohl degradation?

Accepted Answer

It decreases the carbon chain of an aldose by one carbon.

Question 17

Which of the following is a correct statement about glycosides?

Accepted Answer

They are formed by the reaction of a sugar with an alcohol under acidic conditions.

Question 18

Which of the following is the sugar component of RNA?

Accepted Answer

D-ribose

Question 19

Which of the following best describes the difference between pyranose and furanose forms of sugars?

Accepted Answer

Pyranose is a six-membered ring, furanose is a five-membered ring.

The Organic Chemistry of Carbohydrates: Structure, Stereochemistry, and Reactivity

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