REACTIONS OF CARBOHYDRATES (Activity 2b)

Question 1

Formation of yellow crystal, differentiation of reducing sugars

Answer 1

Osazone test

Question 2

Formation of brick red precipitate after boiling, presence of reducing sugar and non reducing sugars

Answer 2

Fehling’s test

Question 3

Formation of brick red precipitate, (blue-green-yellow-orange-red), test for simple carbohydrates and presence of reducing sugars

Answer 3

Benedict’s test

Question 4

Formation of brick red precipitate after 2min of boiling, test for, reducing monosaccharides

Answer 4

Barfoed’s test

Question 5

Why do glucose and fructose form the same osazone crystals

Answer 5

Configuration of C1 and C2 atoms that vanishes after hydrolysis, hence they form the same crystal

Question 6

Difference between benedic’ts and fehling’s

Answer 6

sa alkaline condition ang benedict tapos acidic condition ang barfoed

para madetect ang reducing monosaccharide tapos ang barfoed para i differentiate ang mono vs di

Question 7

Reduction tests, contains cupric ion

Answer 7

Fehling’s, Benedict’s and Barfoed’s

Question 8

phenyl hydrazine hydrochloride, sodium acetate, acetic acid

Answer 8

Osazone test

Question 9

Difference between benedict and barfoed

Answer 9

benedicts - reducing sugar

barfoeds - mono or di

Question 10

cupric acetate, acetic acid

Answer 10

barfoed’s

Question 11

anhydrous sodium carbonate, sodium citrate, copper (ii) sulfate

Answer 11

benedict’s

Question 12

copper ii sulfate (a), sodium potassium tartrate (b)

Answer 12

fehling’s

Question 13

sodium acetate, phenylhydrazinehcl

Answer 13

ozaone

Question 14

bundle of hay crystals

Answer 14

glucose, fructose

Question 15

scattered crystals

Answer 15

xylose

Question 16

sunflower crystal

Answer 16

maltose

Question 17

cotton ball crystal

Answer 17

lactose

Question 18

broad needle crystal

Answer 18

galactose