$$ \mathrm{R{-}CHO} + 2\ \mathrm{H_2$} \xrightarrow{\text{catalyst}} \mathrm{R{-}CH_2OH} $$

Question 1

Which functional group in an aldose monosaccharide is reduced during the formation of a sugar alcohol?

Accepted Answer

The aldehyde group

Question 2

What is the general chemical equation for the reduction of an aldose monosaccharide to a sugar alcohol?

Accepted Answer

$$ \mathrm{R{-}CHO} + 2\ \mathrm{H_2$} \xrightarrow{	ext{catalyst}} \mathrm{R{-}CH_2OH} $$

Question 3

Which reagent is commonly used as a reducing agent in the reduction of monosaccharides to sugar alcohols?

Accepted Answer

$$ \mathrm{H_2$} $$ with a metal catalyst

Question 4

When D-glucose is reduced, what is the name of the sugar alcohol produced?

Accepted Answer

D-glucitol (sorbitol)

Question 5

Which structural change occurs to D-mannose when it is reduced to its corresponding sugar alcohol?

Accepted Answer

The aldehyde group at C1 is converted to a primary alcohol group

Question 6

What is the correct IUPAC suffix for naming a sugar alcohol derived from a monosaccharide?

Accepted Answer

-itol

Question 7

If D-galactose is reduced, what is the common name of the sugar alcohol produced?

Accepted Answer

D-galactitol

Question 8

A patient with diabetes is given a sweetener that is a sugar alcohol derived from glucose. Which compound is most likely being used?

Accepted Answer

Sorbitol

Question 9

Which of the following best describes the reduction of a ketose monosaccharide?

Accepted Answer

The ketone group is reduced to a secondary alcohol group

Question 10

What is the product when D-ribose is reduced using $$ \mathrm{H_2$} $$ and a catalyst?

Accepted Answer

D-ribitol

Question 11

Which of the following statements about the reduction of monosaccharides is correct?

Accepted Answer

Reduction converts the carbonyl group to a hydroxyl group, forming a sugar alcohol

Question 12

Which sugar alcohol is formed from the reduction of D-mannose?

Accepted Answer

Mannitol

Question 13

A chemist reduces D-xylose using $$ \mathrm{H_2$} $$ and a nickel catalyst. What is the product?

Accepted Answer

Xylitol

Question 14

Which of the following is a correct Fischer projection for the sugar alcohol produced from the reduction of D-glucose?

Accepted Answer

$$ \mathrm{CH_2OH{-}(CHOH)_4{-}CH_2OH} $$

Question 15

Which of the following best explains why sugar alcohols are used as sweeteners in sugar-free products?

Accepted Answer

They are less readily metabolized by oral bacteria, reducing the risk of cavities

Question 16

Which of the following is the correct name for the sugar alcohol produced from the reduction of D-galactose?

Accepted Answer

Galactitol

Question 17

A biochemist wants to produce a sugar alcohol from D-mannose. Which reagent should be used?

Accepted Answer

$$ \mathrm{H_2$} $$ and a metal catalyst

Question 18

Which of the following is a correct description of the change in oxidation state for the carbonyl carbon during the reduction of an aldose?

Accepted Answer

The oxidation state decreases as the carbonyl carbon is reduced to an alcohol

Question 19

Which of the following is the correct product of the reduction of D-ribose?

Accepted Answer

Ribitol

Question 20

Which of the following best describes the naming convention for sugar alcohols derived from monosaccharides?

Accepted Answer

Replace the '-ose' ending with '-itol'

Reduction of Monosaccharides and Sugar Alcohols

Study Guide - Practice Questions