MISC 03 - Tests for Carbohydrates

Question 1

Test used to detect the presence of reducing sugars

Answer 1

Benedict’s test

Question 2

Test used to distinguish monosaccharides from disaccharides

Answer 2

Barfoed’s test

Question 3

Test used to distinguish aldose sugars from ketose sugars

Answer 3

Seliwanoff’s test

Question 4

Test used to identify the presence of pentoses and pentosans, and to distinguish pentoses from hexoses

Answer 4

Bial’s test

Question 5

Test used to detect the presence of galactose and lactose

Answer 5

Mucic acid test

Question 6

Test used to distinguish reducing sugars from each other by the osazones they form with the phenylhydrazide reagent

Answer 6

Phenylhydrazone test

Question 7

Positive test result (Benedict’s test)

Answer 7

Brick-red Cu2O precipitate

Question 8

Positive test result (Barfoed’s test)

Answer 8

Brick-red Cu2O precipitate

Question 9

Positive test result that indicates presence of ketose (Seliwanoff’s test)

Answer 9

Cherry-red condensation product

Question 10

Positive test result that indicates presence of aldose (Seliwanoff’s test)

Answer 10

Yellow to pink condensation product

Question 11

Positive test result (Bial’s test)

Answer 11

Blue-green solution

Question 12

Positive test result (Mucic acid test)

Answer 12

Colorless crystals

Question 13

Positive test result (Phenylhydrazone test)

Answer 13

Formation of precipitate

Question 14

Reagent composed of resorcinol in 6 M HCl

Answer 14

Seliwanoff’s reagent

Question 15

Reagent composed of 5-methylresorcinol in concentrated HCl with a small amount of FeCl3

Answer 15

Orcinol reagent

Question 16

Reagent composed of 2 g phenylhydrazide HCl, 3 g CH3COONa, and 10 mL distilled water

Answer 16

Phenylhydrazide reagent

Question 17

Solution composed of 0.1 M glucose, fructose, xylose, lactose, sucrose, and 1% starch

Answer 17

Carbohydrate solution

Question 18

__________ drops of carbohydrate solution (Formulation used in Benedict’s test)

Answer 18

5 drops

Question 19

__________ mL of Benedict’s reagent (Formulation used in Benedict’s test)

Answer 19

1 mL

Question 20

__________ drops of carbohydrate solution (Formulation used in Barfoed’s test)

Answer 20

5 drops

Question 21

__________ mL of Barfoed’s solution (Formulation used in Barfoed’s test)

Answer 21

1 mL

Question 22

__________ drops of carbohydrate solution (Formulation used in Seliwanoff’s test)

Answer 22

5 drops

Question 23

__________ mL of Seliwanoff’s reagent (Formulation used in Seliwanoff’s test)

Answer 23

1 mL

Question 24

__________ drops of carbohydrate solution (Formulation used in Bial’s test)

Answer 24

5 drops

Question 25

__________ mL of Orcinol reagent (Formulation used in Bial’s test)

Answer 25

1 mL

Question 26

__________ drops of carbohydrate solution (composed of galactose and lactose) (Formulation used in Mucic acid test)

Answer 26

3 drops

Question 27

__________ drops of concentrated HNO3 (Formulation used in Mucic acid test)

Answer 27

3 drops

Question 28

__________ drops of carbohydrate solution (Formulation used in Phenylhydrazone test)

Answer 28

2 drops

Question 29

__________ drops of freshly prepared phenylhydrazide reagent (Formulation used in Phenylhydrazone test)

Answer 29

4 drops