Qualitative tests for Carbohydrates

Question 1

most abundant class of organic compounds found in living
organisms.

Answer 1

Carbohydrates

Question 2

Carbohydrates originate as products of _______.

Answer 2

photosynthesis

Question 3

Primary function of Carbohydrates?

Answer 3

to provide the body with energy (most especially our
brain and nervous tissue)

Question 4

Carbohydrates are also called?

Answer 4

Saccharides

Question 5

Three elements that makes up Carbohydrates

Answer 5

carbon, hydrogen and oxygen

Question 6

True or False: generally insoluble in polar solvents like
water except for polysaccharides

Answer 6

False

Question 7

True or False: Carbohydrates generally soluble in non-polar solvents
like ether

Answer 7

False

Question 8

They only one unit of saccharides in them

Answer 8

Monosaccharides

Question 9

They are also called simple sugar

Answer 9

Monosaccharides

Question 10

They have two units of saccharides in them

Answer 10

Disaccharides

Question 11

The two saccharides are joined together by a __________

Answer 11

glycosidic bond

Question 12

The two saccharides are joined together by a glycosidic bond also known as ______

Answer 12

glycosidic linkage

Question 13

They have more than two units of saccharides in them

Answer 13

Polysaccharides

Question 14

Monosaccharides include?

Answer 14

Glucose and fructose

Question 15

Disaccharides include?

Answer 15

Lactose and sucrose

Question 16

Polysaccharides include?

Answer 16

Starch, glycogen and cellulose

Question 17

Results to violet ring at the junction of 2 liquids

Answer 17

Molisch’s Test

Question 18

Results to Blue-black/ Indigo solution

Answer 18

Lugol’s tests

Question 19

Results to Blue-Green Complex for Pentose and Brown complex for hexose

Answer 19

Bial’s test

Question 20

Results to cherry red product

Answer 20

Seliwanoff’s Test

Question 21

Results to Blue-green color

Answer 21

Anthrone test

Question 22

Sulfuric acid/ H2SO4 dehydrates the sugar to from furfural derivatives then condensed by anthrone to form condensation product

Answer 22

Anthrone test

Question 23

Uses 6M HCl as dehydrating agent to produce hydroxymethyfurfural the addition of resorcinol will prduce a condensation product.

Answer 23

Seliwanoff’s Test

Question 24

HCl dehydrates pentose to form furfural and dehydrates hexoses to form 5- hydroxymethyl furfural. The furfural derivatives are condensed by orcinol and iron ion

Answer 24

Bial’s test

Question 25

Starches contain ɑ-amylose, a helical saccharide polymer and amylopectin. Iodine forms a large polysaccharide complex with the ɑ-amylose helix to yield a colored product

Answer 25

Lugol’s tests

Question 26

Sulfuric Acid/H2SO4 dehydrates pentose to form furfural and dehydrates
hexoses to form 5- hydroxymethyl furfural. The furfural derivatives are condensed by α-naphthol to yield a condensation product

Answer 26

Molisch’s Test

Question 27

Reagent: 10% ɑ-naphthol in ethanol and conc. H2SO4

Answer 27

Molisch’s Test

Question 28

Also known as Potassium Iodide test. Distinguish starch from other carbohydrates

Answer 28

Lugol’s tests

Question 29

Reagent: HCL as dehydrating agent and orcinol with trace Fe3Cl as the condensation reagent

Answer 29

Bial’s test

Question 30

distinguish between aldoses and ketoses

Answer 30

Seliwanoff’s Test

Question 31

Example of Aldose sugar

Answer 31

Glucose

Question 32

Example of ketose sugar

Answer 32

Fructose
Sucrose