Question 1

Cellulose will give a positive Benedict's test.

Accepted Answer

Benedict's test is used to detect reducing sugars, which have a free or potentially free aldehyde or ketone functional group. Cellulose, being a polymer of glucose units linked by beta-1,4-glycosidic bonds, does not have a free or potentially free aldehyde or ketone functional group and therefore does not give a positive Benedict's test.

Question 2

Identify each Fischer projection as the D- or L-isomer.
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Accepted Answer

The answer of Identify each Fischer projection as the D-...

Question 3

Fructose is a ketohexose.

Accepted Answer

Fructose is a monosaccharide that has a ketone functional group at position number 2 and a six-carbon chain, which makes it a ketohexose.

Question 4

Sucrose is a reducing sugar.

Accepted Answer

Sucrose is a disaccharide composed of glucose and fructose units bonded together through a glycosidic linkage. It does not contain a free aldehyde or ketone group that is necessary for a sugar to be classified as a reducing sugar.

Question 5

Fructose is also known as dextrose.

Accepted Answer

Fructose and dextrose are two different types of sugars. Fructose is a type of monosaccharide, while dextrose is another name for glucose, a different type of monosaccharide.

Question 6

The product of oxidation of an aldose is a carboxylic acid.

Accepted Answer

Aldoses are oxidized to form carboxylic acids, specifically aldonic acids. This is because aldoses have a terminal aldehyde group that can be oxidized to a carboxylic acid group.

Question 7

State whether each of these structures is the α- or β-form.
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Accepted Answer

The answer of State whether each of these structures is...

Question 8

A monosaccharide can be hydrolyzed to smaller units.

Accepted Answer

The answer of A monosaccharide can be hydrolyzed to smaller...

Question 9

Identify each Fischer projection as the D- or L-isomer.
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Accepted Answer

The answer of Identify each Fischer projection as the D-...

Question 10

Identify each Fischer projection as the D- or L-isomer.
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Accepted Answer

The answer of Identify each Fischer projection as the D-...

Question 11

A reducing sugar gives a precipitate of silver metal with Benedict's reagent.

Accepted Answer

Benedict's reagent is used to test for reducing sugars, but it does not produce a precipitate of silver metal; instead, it gives a precipitate that is typically green, yellow, orange, red, or brown, depending on the amount of reducing sugar present. The formation of a silver metal precipitate is characteristic of the Tollens' test, not Benedict's test.

Question 12

State whether each of these structures is the α- or β-form.
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Accepted Answer

The answer of State whether each of these structures is...

Question 13

Identify each Fischer projection as the D- or L-isomer.
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Accepted Answer

The answer of Identify each Fischer projection as the D-...

Question 14

In the α anomer of glucose, the OH on carbon 1 is above the plane of the ring.

Accepted Answer

The answer of In the α anomer of glucose, the...

Question 15

Identify each Fischer projection as the D- or L-isomer.
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Accepted Answer

The answer of Identify each Fischer projection as the D-...

Question 16

Maltose is a reducing sugar.

Accepted Answer

Maltose has a free anomeric carbon that can act as a reducing agent, thus it is classified as a reducing sugar.

Question 17

The product of reduction of mannose is mannic acid.

Accepted Answer

The product of reduction of mannose is mannitol.

Question 18

State whether each of these structures is the α- or β-form.
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Accepted Answer

The answer of State whether each of these structures is...

Question 19

State whether each of these structures is the α- or β-form.
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Accepted Answer

The answer of State whether each of these structures is...

Question 20

State whether each of these structures is the α- or β-form.
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Accepted Answer

The answer of State whether each of these structures is...

Quiz 15: Carbohydrates

Cellulose will give a positive Benedict's test.

Identify each Fischer projection as the D- or L-isomer. -

Fructose is a ketohexose.

Sucrose is a reducing sugar.

Fructose is also known as dextrose.

The product of oxidation of an aldose is a carboxylic acid.

State whether each of these structures is the α- or β-form. -

A monosaccharide can be hydrolyzed to smaller units.

Identify each Fischer projection as the D- or L-isomer. -

Identify each Fischer projection as the D- or L-isomer. -

A reducing sugar gives a precipitate of silver metal with Benedict's reagent.

State whether each of these structures is the α- or β-form. -

Identify each Fischer projection as the D- or L-isomer. -

In the α anomer of glucose, the OH on carbon 1 is above the plane of the ring.

Identify each Fischer projection as the D- or L-isomer. -

Maltose is a reducing sugar.

The product of reduction of mannose is mannic acid.

State whether each of these structures is the α- or β-form. -

State whether each of these structures is the α- or β-form. -

State whether each of these structures is the α- or β-form. -