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STUDENT WORKSHEET ORGANIC CHEMISTRY PRACTICE "CARBOHYDRATE"
Name
: Era Melania
Class
: PKU 2018
Reg. Number
: 18030194085
Chemistry Department Faculty of Mathematics and Natural Science Surabaya State University 2020
Phase 1: Orientation Task 1 a. Equipments which is needed No. Equipments/Materials
Spesification
Function
1.
20 pieces
To react a small
Test tube and rack
amount
of
substances 2.
Pipette
20 pieces
Help to move chemical solution
from
one container to another
on
a
small scale 3.
Measuring flask
2 pieces
To measure a volume
of
liquid substances 4.
Beaker glass
1 piece of 250 Use mL
as
container
1 piece of 600 heat mL
a to
chemical
substances
or
react a larger quantities
of
substances 5.
Spirtus burner
1 piece
To
heat
chemical substances 6.
Tripod/Three-legged
1 piece
To
hold
the
gauze
mats
during
the
heating process 7.
Gauze mats
1 piece
As
a base in
heating process 8.
Wood clamp
1 piece
To hold a hot equipment
9.
2% of glucose
22 drops
As carbohydrate sample
10.
Sucrose
1 mL
As carbohydrate sample
11.
Starch
3 mL
As carbohydrate sample
12.
Lactose
17 drops
As carbohydrate sample
13.
Watery ammonia (in Tollens Sufficienly
To
form
test)
Ag(NH3)2OH complex ion
14.
HCl 3M (in sucrose and 3 mL
As catalys
starch hydrolysis)
b. Reagents that needed No
1.
Experiment tittle/ subtittle Molish Test
Reagent Used Molish reagent
Function of Reagent To test the presence of carbohydrate compound in sample
Reaction Sucrose HO HO OH
O
CH2OH
O
H
O
H2O, H+
O
HO
OH
OH
Kalor
OH H
Concenrated H2SO4
To avoid and form hydrolysis or break down disaccharide molecules into
HO
+
H
OH OH
CH2OH
H
OH
OH
H
H
CH2OH
OH OH
Sukrosa
Step 1
Glukosa
OH
O
H
Fruktosa
monosaccharides and polysaccharides into disaccharides
H2O, H+
+2 + 3H2O
+2
→ Kompleks berwarna ungu Glucose H2O, H+
+2 + 3H2O
+2
→
Kompleks berwarna ungu Amylum Step 1: Hydrolisis amylum to glucose
+
Step 2:
n
H2O, H+
+2 + 3H2O
+2
→
Kompleks berwarna ungu 2.
Seliwanoff Test
Seliwanoff reagent
To distinguish between alldose and ketose sugar
Amylum
Glucose
Lactose
3.
Barfoed Test
Barfoed reagent
To differentiate monosaccharides and disaccharides from the samples
Amylum CH2OH
CH2OH H
O H H H OH
H
H
OH
O H H OH
H
H
OH
O
O
*O
+ 2Cu2+ + 2H2O n
amilum
Glucose
CH2OH
CH2OH
O H
H
O
H2 O
H
OH
H
C H + 2Cu2+ + 2H O 2
OH OH
OH
OH
OH
OH
Glukosa
CH2OH
COO-
OH
+ Cu2O Endapan merah bata
OH OH
Lactose OH
CH2OH
CH2OH O
O
O
OH
+ 2Cu2+ + 2H2O
OH OH OH
OH
Laktosa
4.
Tollens Test
Tollens reagent
Sucrose
To differentiate reduction sugar and non-reduction sugar
HO HO OH
O O
O
OH
HO
HO
OH
fructose
glucose OH
sucrose
CH2OH
+
[Ag(NH3)2]
OH CO2-
OH
+ Ag
OH OH
Amylum
+ Ag(NH3)2OH (aq) ↛ (aq)
Lactose
Ag(NH3)2+ OH-
(aq) Glucose
(aq)
+ Ag (s) silver mirror NaOH solution
To form a brown
2 AgNO3 (aq) + 2 NaOH (aq) →
silver precipitate.
Ag2O (s) + 2 NaNO3 (aq) + H2O(l) (brown precipitate)
NH4OH solution
To dissolve the silver oxide precipitate by forming a complex compound or oxidizing the
Ag2O (s) + 2 NH4OH (aq) → 2Ag(NH3)2OH (aq)
5.
Fehling Test
Fehling reagent
Ag2O compound To test the presence of reducing sugars in the sample
Fructose
+ (aq) +
Cu2+ →
(aq) + Cu2O(s) (brick red) Lactose
(aq) + 2Cu2+ →
+ Cu2O(s) (Brick red) Glucose
6.
Sucrose hydrolysis
HCl solution
To break down sucrose into glucose and fructose
H+, OH-
+
Benedict reagent
To test for sucrose with a brick red precipitate
Glucose
(aq) + Cu2+ (aq) →
+ (aq) + Cu2O (s)
Fructose
(aq) + Cu2+ →
(aq) + Cu2O (s) Seliwanof reagent
To test for ketosa groups
3H2O, H+
7.
Hidrolisis pati
Iodine
To identify hydrolyzed starch or not + n I2 →
n + 2 H2O (l) tidak terhidrolisis
+ I2 Terhidrolisis Benedict reagent
To test for sucrose with a brick red precipitate
+ Cu2+ (aq) →
(aq) + Cu2O (s) + 3H2O (l)
Phase 2: Conceptualization Task 2 1. Molisch Test a. Purpose and Formulation of the Problem/question Purpose Identify carbohydrate functional groups in the sample Formulation of the Problem/question Does the sucrose sample contain carbohydrates? Does the glucose sample contain carbohydrates? Does the starch sample contain carbohydrates? b. Hypothesis Sucrose, glucose and starch samples contain carbohydrates 2. Seliwanoff Test a. Purpose and Formulation of the Problem/question Purpose To prove the ketose in compund by using seliwanoff reagent Formulation of the Problem/question How the positive result that shown from seliwanoff test? b. Hypothesis In this test the positive result is in succrose and fructose as the sample that mixed with seliwanoff reagent then heated. It will produce red orange solution that identify the presence of ketose in monosaccharide type in carbohidrate 3. Barfoed Test a. Purpose and Formulation of the Problem/question
Purpose To know the presence of reducing monosaccharides and disaccharide by using barfoed test Formulation of the Problem/question How is the positive indication of barfoed test? b. Hypothesis Foodstuffs which containing monosaccharides will produce brick red precipitate after heated for 2 minutes Foodstuffs which containing disaccharides will produce brick red precipitate after being heated for 10 minutes 4. Tollens Test a. Purpose and Formulation of the Problem/question Purpose To recognize compound belonging to carbohydrates through tollens test Formulation of the Problem/question How the changes that occur in carbohydrates taht contain aldehyde and ketone groups when reacted with tollens reagents? b. Hypothesis Carbohydrates that contain aldehyde groups when reacted with tollens reagents will form silver mirror, whereas carbohydrates with the ketones groups do not react 5. Fehling Test a. Purpose and Formulation of the Problem/question Purpose: To identify the presence of reducing sugars in the sample Formulation of the Problem/question: 1. What is the definition of reducing sugar? 2. What is the example of reducing sugar? 3. What is the properties of reducing sugar? b. Hypothesis
The solution that contain a reducing sugar will form a brick red precipitate 6. Hydrolysis of Sucrose a. Purpose and Formulation of the Problem/question Purpose: To hydrolysis sucrose molecule become maltose and glucose that will test with benedict and seliwanoff Formulation of the Problem/question What is the reaction that occur in the hydrolysis of sucrose? b. Hypothesis 1. The presence of reducing sugar if tested with benedict reagent will produce brick red precipitate 2. The presence of ketosa groups if tested with seliwanoff reagent will produce red or orange solution 7. Hydrolysis of Pati a. Purpose and Formulation of the Problem/question Purpose 1. Hydrolyze polysaccharides 2. Testing the results of the polysaccharide hydrolysis use iodine and benedict test. Formulation of the Problem/question 1. How to do hydrolysis of polysaccharides? 2. How to test the results of the polysaccharide hydrolysis use iodine and benedict test? b. Hypothesis 1. Polysaccharide which has been hydrolyzed is tested with iodine then no reaction will occur 2. Polysaccharide which has been hydrolyzed is tested with benedict will form a brick red precipitate
Phase 3: Investigation Task 3 1. Molisch Test Variables: Control variable: 2 drops of Molisch reagents 7-8 drops of H2SO4 concentrated Manipulation variable: The types of carbohydrate (sucrose, glucose, amylum) Response variable: The result of Molisch test of sucrose, glucose, amylum Procedure: 2,5 drops of sucrose
2,5 drops of glucose
2,5 drops of starch
1. Added 5 drops of molish reagent 2. Added 10 drops of concentrated sulfuric acid until forms a separate layer from the initial layer
If there is carbohydrate formed a red ring then turns dark purple
3. Leave for 2 minutes 4. Added 5 ml of water
Purple Formed
2. Seliwanoff Test
Variables: Controlled Variable: 5 drops of seliwanof reagent, shake and heated the mixture on a water bath Manipulation Variable: sampel test (lactose, glucose, amylum) Response Variable: time needed to color changes Procedure 1. Test tube 1 5 drops of lactose 1. Added 5 drops of seliwanoff reagent 2. Shake and heated the mixture on a water bath 3. Note the time needed to colour changes Result 2. Test tube 2 5 drops of glucose 1. Added 5 drops of seliwanoff reagent 2. Shake and heated the mixture on a water bath 3. Note the time needed to colour changes Result 3. Test tube 3 5 drops of amylum 1. Added 5 drops of seliwanoff reagent 2. Shake and heated the mixture on a water bath 3. Note the time needed to colour changes Result
3. Barfoed Test Variables: Control Variable: 5 mL of barfoed reagent 5 drops of sample Heated the mixture on a water bath Manipulation Variable: sampel test (lactose, glucose, amylum) Response Variable: There is red brick precipitate Procedure Test Tube 1
Test Tube 2
Test Tube 3
5 mL of Barfoed reagent
5 mL of Barfoed reagent
5 mL of Barfoed reagent
- Added 5 ml of amylum - Heated in a water bath - Wait for 2 minutes
- Added 5 ml of glucose - Heated in a water bath - Wait for 2 minutes
- Added 5 ml of lactose - Heated in a water bath - Wait for 2 minutes
- Observed changes that occur
- Observed changes that occur
- Observed changes that occur
Result
Result
- Wait for 10 minutes
- Wait for 10 minutes
- Observed changes that occur
- Observed changes that occur
Result
4. Tollens Test Variables:
Result
Result - Wait for 10 minutes - Observed changes that occur Result
a. Controlled variable: 5 drops of tollens reagent. b. Manipulation Variables: Various of carbohydrate (sucrose, lactose, amylum, glucose, and fructose). c. Response
variable: Tollens test results for each type of (sucrose,
lactose, amylum, glucose, and fructose). Procedure Making of Tollens Test 1 mL of AgNO3 Solution 1. Put into a test tube 2. 1 mL of NaOH solution is added 3. Mixed Tollens Reagent Tollens Test
2-5 drops of starch
2-5 drops of sucrose
2-5 drops of lactose
2-5 drops of glucose
1. Putted into each test tube 2. Added 5 drops of Tollens reagent 3. Added aqueous ammonia solution drop by drop until all precipitate has dissolved 4. Heated the mixture if no silver mirror is formed
Formed silver mirror 5. Fehling Test Variables: Control variable: Number of drops. Response variable: Color change. Manipulation variable: Sugar solution (sucrose and glucose) Procedure
Making Reagent Fehling Fehling A 1 mL
1. Add fehling B 1 mL Fehling reagent
Test Tube I 2 drops of sucrose
Test Tube II Test Tube III Test Tube IV Test Tube V 2 drops of lactose
2 drops of amylum
2 drops of glucose
1. Add 2 drops of fehling reagent 2. Shake it and heat it Red precipitate
6. Hydrolysis of Sucrose Variables: a. Controlled variable: • 0.5 mL of sucrose b. Manipulation Variable: • Added 1 mL HCl • Added 1 mL of water • Heated and cooled at room temperature • Left at room temperature • Added 1.5 mL NaOH • Types of reagents c. Response variable: sucrose test results from each tube Procedure 0,5 mL sucrose - Dissolved in water Sucrose solution
2 drops of fructose
1 mL Sucrose solution (1) - Added 1 mL HCl 3 M - Boiled in water bath - Cooled at room temperature
- Added 1,5 mL sucrose solution Test tube 1A
Test tube 1B
- Added 5 mL Benedict’s reagen
- Added 2 mL Seliwanof’s reagen
- Boiled in water bath for 5 minutes
- Boiled in water bath for 5 minutes
Result
Result
1 mL Sucrose solution (2) - Added 1 mL water
- Boiled in water bath - Cooled at room temperature - Added 1,5 mL sucrose solution Test tube 1A
Test tube 1B
- Added 5 mL Benedict’s reagen
- Added 2 mL Seliwanof’s reagen
- Boiled in water bath for 5 minutes
- Boiled in water bath for 5 minutes
Result
Result
1 mL Sucrose solution (3) - Added 1 mL water - Cooled at room temperature - Added 1,5 mL water - Divided into 2 test tube equally
Test tube 1A
Test tube 1B
- Added 5 mL Benedict’s reagen
- Added 2 mL Seliwanof’s reagen
- Boiled in water bath for 5 minutes
- Boiled in water bath for 5 minutes
Result
Result
7. Hydrolysis of Pati Variables: Control variable Volume of starch (amylum) solution Volume of benedict reagents Iodine test Manipulation variable The addition of 2 ml of HCl 3 M, 2 ml of water and 3 ml of NaOH 3 M Heated in a water bath Cooled at room temperature Response variable Changes that occur in all three solutions in the test tube Procedure
2 ml of pati (amylum) solution 1. Added 2 ml of HCl 3M 2. Heated in steam bath 3. Cooled in room temperature 4. Added 3 ml of NaOH 3M 5. Divided into 2 test tube 1b
1a 6. Iodine test
6. Added 5 ml of Benedict reagent
Result
Result
2 ml of pati (amylum) solution 1. Added 2 ml of water 2. Heated in steam bath 3. Cooled in room temperature 4. Added 3 ml of water 5. Divided into 2 test tube 2b
2a 6. Iodine test
Result
6. Added 5 ml of Benedict reagent
Result
2 ml of pati (amylum) solution 1. Added 2 ml of water 2. Let it in room temperature 3. Added 3 ml of water
3b
3a 4. Iodine test
Result
4. Added 5 ml of Benedict reagent
Result
Table 1.4.1 Molisch Test Observation Data No
Procedure
Observation Before
1
Test Tube 1
2,5 drops of Sucrose 1. Added 5 drops of Molisch reagent 2. Added 10 drops of concentrated Sulfuric acid until forms a separate layer from the initial layer If there is carbohydrate formed a red ring then turns dark purple
Sucrose :
2,5 drops of
colorless
sucrose + 5
solution
drops of
Molisch
molisch reagent
reagent :
: clear turbid
brownish
solution
solution
After
2,5 drops of
H2SO4
sucrose + 5
concentrated :
drops of
colorless
molisch reagent
solution
+ 10 drops of concentrated H2SO4 : there
3. Leave for 2 minutes 4. Added 5 mL of water
are 2 layer (red
Purple formed
ring in lower layer)
2,5 drops of sucrose + 5 drops of molisch reagent + 10 drops of concentrated H2SO4 + 5 mL of water : purple ring in solution
Test Tube 2
2,5 drops of Glucose 1. Added 5 drops of Molisch reagent 2. Added 10 drops of concentrated Sulfuric acid until forms a separate layer from the initial layer If there is carbohydrate formed a red ring then turns dark purple
Glucose :
2,5 drops of
colorless
glucose + 5
solution
drops of
Molisch
molisch reagent
reagent :
: clear turbid
brownish
solution
solution
2,5 drops of
H2SO4
glucose + 5
concentrated :
drops of
colorless
molisch reagent
solution
+ 10 drops of concentrated
5. Leave for 2 minutes 6. Added 5 ml of water
H2SO4 : there are 2 layer (red
Purple formed
ring in lower layer)
2,5 drops of glucose + 5 drops of molisch reagent + 10 drops of concentrated H2SO4 + 5 mL of water : purple ring in solution
Test tube 3
2,5 drops of Amylum 1. Added 5 drops of Molisch reagent 2. Added 10 drops of concentrated Sulfuric acid until forms a separate layer from the initial layer If there is carbohydrate formed a red ring then turns dark purple
Amylum :
2,5 drops of
colorless
amylum + 5
solution
drops of
Molisch
molisch reagent
reagent :
: clear turbid
brownish
solution
solution
2,5 drops of
H2SO4
amylum + 5
concentrated :
drops of
colorless
molisch reagent
solution
+ 10 drops of concentrated
3. Leave for 2 minutes 4. Added 5 ml of water
H2SO4 : there are 2 layer (red
Purple formed
ring in lower layer)
2,5 drops of amylum + 5 drops of molisch reagent + 10 drops of concentrated H2SO4 + 5 mL of water : purple ring in solution
Table 1.4.2 Seliwanof Observation Data No
Procedure
Observation Before
1
Test Tube 1
5 drops of amylum -
-
Added 5 drops of seliwanoff reagent Shake and heated the mixture on a water bath Note the time needed to colour changes
Amylum ,
After
5 drops of
colorless
starch + 5 drops
solution
of seliwanoff
Seliwanoff
reagent, a
reagent, a
yellowish
yellowish
solution
solution
5 drops of starch + 5 drops of seliwanoff + reagent + heated,
Result
yellowish solution (does not change color)
2 5 drops of lactose -
-
Added 5 drops of seliwanoff reagent Shake and heated the mixture on a water bath Note the time needed to colour changes
Result Test Tube 2
Lactose,
5 drops Lactose +
colorless
5 drops
solution
seliwanoff
seliwanoff
reagent, a
reagent, a
yellowish
yellowish
solution
solution
5 drops Lactose + 5 drops seliwanoff reagent + heated, yellowish solution (does not change color)
3
Test tube 2
5 drops of glucose -
-
Added 5 drops of seliwanoff reagent Shake and heated the mixture on a water bath Note the time needed to colour changes
Result
Glucose,
5 drops of
colorless
glucose + 5
solution
drops of
Seliwanoff
seliwanoff
reagent, a
reagent, a
yellowish
yellowish
solution
solution
5 drops of glucose + 5 drops of seliwanoff reagent + heated, yellowish solution (does not change color
Table 1.4.3 Barfoed Test Observation Data NO 1
Line Work Test Tube 1 5 mL of Barfoed reagent
- Added 5 ml of amylum - Heated in a water bath - Wait for 2 minutes - Observed changes that occur
Result of observation Before
After
- Barfoed reagent : - Amylum + blue solution
Barfoed and
- Amylum:
heated : blue
Colorless solution
solution
- Lactose: Colorless solution - Glucose: Colorless solution
Result
- Wait for 10 minutes - Observed changes that occur Result Test Tube 2 5 mL of Barfoed reagent
- Glucose + Barfoed and heated : blue solution
- Added 5 ml of glucose - Heated in a water bath - Wait for 2 minutes - Observed changes that occur
Result
- Wait for 10 minutes - Observed changes that occur Result
Test Tube 3 5 mL of Barfoed reagent
- Lactose + Barfoed and heated : blue solution
- Added 5 ml of lactose - Heated in a water bath - Wait for 2 minutes - Observed changes that occur Result
- Wait for 10 minutes - Observed changes that occur Result
Table 1.4.4 Tollens Test Observation Data No
Observation
Treatment Test Tube 1
5 drops of Lactose Sample 1. Added 5 drops of Tollens reagent 2. Heated If no silver mirror is formed Result
Test Tube 2
5 drops of Sucrose Sample
Before
Tollens reagent: colorless Lactose: colorless Sucrose: colorless Glucose: colorless Amylum: colorless
After
1. Added 5 drops of Tollens reagent 2. Heated If no silver mirror is formed
Lactose + Tollens: brownish brown Lactose + Tollens + heated: silver mirror formed
Sucrose + Tollens: colorless Sucrose + Tollens + heated: silver mirror formed
Result Test Tube 3
5 drops of Glucose Sample 1. Added 5 drops of Tollens reagent 2. Heated If no silver mirror is formed Result
Glucose + Tollens: black Glucose + Tollens + heated: silver mirror formed
No
Treatment Test Tube 4
5 drops of Amylum Sample 1. Added 5 drops of Tollens reagent 2. Heated If no silver mirror is formed Result
Observation Before
After Amylum + Tollens: pace brown Amylum + Tollens + heated: colorless
Table 1.4.5 Fehling Test Observation Data No. 1.
Line Work Making Reagent Fehling Fehling A 1 mL 1. Add fehling B 1 Fehling reagent
Observation Result Before - Fehling
A
After : Fehling
A
+
Colorless
Fehling B : Blue
solution
solution
- Fehling
B
:
Blue solution 2.
Sucrose Test 2 drops of Sucrose 1. Add 2 drops of Fehling reagent Result
3.
Lactose Test 2 drops of Lactose 1. Add 2 drops of Fehling reagent Result
4.
Amylum Test 2 drops of Amylum 1.
Add 2 drops of Fehling reagent
Result 5.
Glucose Test 2 drops of Glucose 1. Add 2 drops of Fehling reagent Result
6.
Fructose Test
- Sucrose
: Sucrose + Fehling
Colorless
reagent
solution
solution
:
Blue
- Fehling reagent : Blue solution - Lactose
: Lactose + Fehling
Colorless
reagent
:
solution
precipitate
Red
- Fehling reagent : Blue solution - Amylum
: Amylum
+
Colorless
Fehling reagent :
solution
Blue solution
- Fehling reagent : Blue solution - Glucose
: Glucose
+
Colorless
Fehling reagent :
solution
Red precipitate
- Fehling reagent : Blue solution
- Fructose
: Fructose
+
No.
Line Work 2 drops of Fructose 1. Add 2 drops of Fehling reagent Result
Observation Result Before
After
Colorless
Fehling reagent :
solution
Red precipitate
- Fehling reagent : Blue solution
Table 1.4.6 Sucrose Hydrolysis Observation Data No.
Line work
1. 0,5 mL sucrose - Dissolved in water Sucrose solution
2.
Test tube 1
Result of Observation Before After - Sucrose : - Sucrose + aquades : colorless sucrose - Aquades : solution colorless
Test tube 1
Test tube 1
- Sucrose
-
Sucrose
1 mL Sucrose solution (1)
solution:
solution +
- Added 1 mL HCl 3 M
colorless
HCl
- Boiled in water bath
solution
solution
- Cooled at room temperature - Added 1,5 mL sucrose solution Test tube 1B Test tube 1A - Added 2 mL - Added 5 mL Benedict’s Seliwanof’s reagen reagen - Boiled in water bath for 5 - Boiled in water bath minutes for 5 minutes - Observed the changes that occur - Observed the changes that occur Result Result
- HCl solution
colorless :
colorless solution - NaOH
solution -
Sucrose solution + HCl
solution:
solution :
colorless
a. after
solution - Benedict reagent: blue solution -
:
Seliwanoff Reagen: colorless solution
heating : colorles s solutio n b. after heating and cooling : colorles s
solutio n -
sucrose solution + HCl solution + heating and cooling
+
NaOH solution
:
colorless solution Test tube 1a - solution in test tube 1 + benedict reagent
:
blue solution - solution in test tube 1 + benedict reagent
+
heating: blue greenish solution and
brick
red percipatate formed Test tube 1b
- solution in test tube 1+ Seliwanoff reagent
:
colorless solution -
solution in test
tube
1+ seliwanof reagen
+
heating: clear yellow solution. Test tube 2
Tabung 2
1 mL Sucrose solution (2)
-
- Added 1 mL water
solution
- Boiled in water bath - Cooled at room temperature
Test tube 2A
- Added 5 mL Benedict’s reagen - Boiled in water bath for 5 minutes - Observed the changes that occur
sucrose
Test tube 2B
- Added 2 mL Seliwanof’s reagen - Boiled in water bath for 5 minutes
Result
:
solution + aquades
solution
colorless
colorless
:
:
solution -
Sucrose
solution
solution +
- NaOH
aquades :
solution :
- After heating:
colorless
colorless
solution
solution
- Benedict Result
a. Sucrose
colorless
-aquades
- Added 1,5 mL sucrose solution
Tabung 2
Reagent : blue solution
-
After heating + cooling colorless solution
:
-
Seliwanoff Reagent : colorless solution
sucrose solution + aquades + heating and cooling + NaOH solution : colorless solution
-
sucrose solution + aquades + heating and cooling + NaOH
+
aquades: colorless solution Test tube 2a -
solution in test tube 1 + benedict reagent
:
blue solution -
solution in test tube 1 + benedict reagent + heating:
clear blue greenish solution and brick red precipitate formed Test tube 2b -
solution in test tube 1 + Seliwanoff reagent
:
colorless solution -
solution in test tube 1 + Seliwanoff reagent + heating clear yellow solution.
:
Test tube 3
-
Sucrose solution : colorless solution
-
Aquades : colorless solution
1 mL Sucrose solution (3) - Added 1 mL water - Cooled at room temperature - Added 1,5 mL water Test tube 3B
Test tube 3A
- Added 5 mL Benedict’s reagen - Boiled in water bath for 5 minutes - Observed the changes that occur Result
- Added 2 mL Seliwanof’s reagen
-
HCl : colorless solution
-
NaOH : colorless solution
-
Benedict Reagent : blue solution
-
Seliwanoff Reagent : colorless solution
- Boiled in water bath for 5 minutes
- Observed the changes that occur Result
Test tube 3 Sucrose solution + aquades : colorless solution -
-
-
-
Sucrose solution + aquades + placed at room temperatur e: colorless solution Sucrose solution + aquades + placed at room temperatur e + aquades : colorless solution Test tube 3a Solution in test tube 3 + R. Benedict : blue solution
- Solution in test tube 3 + Benedict reagent + heating : blue greenish solution Test tube 3b - Solution in test tube 3+
aquades : colorless solution -
Solution in test tube 3+ aquades + placed at room temperatur e: colorless solution
-
Solution in test tube 3+ aquades + placed at room temperatur e+ aquades : colorless solution
-
Solution in test tube 3+ aquades + placed at room temperatur e+ aquades+ Seliwanoff R: clear yellow solution
-
Solution in test tube 3+ aquades + placed at room temperatur
e+ aquades+ Seliwanoff R+ heating : clear yellow solution
Table 1.4.7 Pati Hydrolysis Observation Data No.
Observation
Treatment
1.
Before
-
Tube 1
Starch
After
-
2 mL
Solution:
Starch
Colorless
solution + 2
solution
mL HCl
HCl
solution =
2. Put the tube on the water bath
solution:
Colorless
3. Cooled at room temperature
Colorless
solution.
4. Add 3 mL of NaOH 3 M
solution
2 mL of starch solution 1. Added 2 mL of 3 M HCl solution
-
-
-
Put on a
3 M NaOH
water bath
Divided the solution into 2
Solution:
= colorless
tubes with the same volume
Colorless
solution
Solution
Tube 1A
5. Add enough iodine Result
Solution Tube 1B
-
6. Put 5 mL of benedict reagent
-
+ 3 mL
Iodine
NaOH =
Solution:
colorless
yellowish
solution
brown Result
-
-
Solution 1A
Benedict
+ Iodine =
reagent:
Colorless
blue
solution
solution
-
Solution 1B + 5 mL Benedict reagent = Blue solution
2.
-
Tube 2 2 mL of starch solution 1. Added 2 mL of water 2. Put the tube on the water bath 3. Leave it at room temperature 4. Add 3 mL of water
-
Divided the solution into 2 tubes with the same volume Tube 2A 5. Add enough iodine
Result
6. Enter 5 mL of benedict reagent
Result
-
2 mL Starch
Colorless
solution + 2
solution
mL Water =
Water: A
colorless
colorless
solution -
Put on
Iodine
water bath
Solution:
= colorless
yellowish
solution
brown Tube 2B
-
Solution:
solution -
Solution
Starch
-
Refrigerate
Benedict
d at room
reagent:
temperature
blue
= Colorless
solution
solution -
+ 3 mL Water = Colorless solution
-
Solution 2A + Iodine = Blue solution
-
Solution 2B + 5 mL Benedict reagent = Blue solution
3.
- Starch
-
2 mL
Tube 3
Solution:
Starch
2 mL of starch solution
Colorless
solution +
solution
2 mL
1. Added 2 mL of water 2. Leave it at room temperature 3. Add 3 mL of water
- Water: colorless
colorless
solution
solution.
- Iodine Solution Divided the solution into 2 tubes with the same volume
Tube 3A 4. Add enough iodine
Result
Tube 3B 5. Put 5 mL of benedict reagent
Water =
-
Leave it at
Solution:
room
yellowish
temperatur
brown
e=
- Benedict
colorless
reagent: blue
solution -
solution
+ 3 mL Water = Colorless
Result
solution -
Solution 3A +
Iodine = Dark blue solution -
3B solution + 5 mL Benedict reagent = Blue solution
Task 5 1. Molisch Test a. Reaction The reaction is as follows: Sucrose reaction
Sucrose
Glucose
5-hydroxymethyl furfural
Purple compound
Fructose
α-naphthol
Purple compound
1) Glucose reaction
Glucose
5-hydroxymethyl furfural
α-naphthol
Purple compound 2) Reaction Starch
Starch
Glucose
Purple compound 3) Fruktosa Reaction
Glucose
5-hydroxymethyl furfural
naftol
Purple compound
4) Lactose Reaction
Lactose
5-hydroxymethyl furfural
-naftol
Purple compound b. Explanation In this experiment we applied the principle of molisch test. The principle of the molisch test is a reaction of carbohydrate dehydration by sulfuric acid or H2SO4 to form a complementary ring or hydroxyl methyl hydroxide when reacting with α-naftol present in the reagent. If in the snippet there is a carbohydrate, a red ring will form on the bottom layer. The red will soon turn into a dark purple. Once dried and diluted with water it will turn purple. First, the extracts (sucrose, glucose, and amylum) were added for 2-5 drops and 5 drops of Molisch reaction. Then put 7-10 drops of concentrated sulfuric acid into the base of the tube with a drop of pipes in such a way that sulfuric acid forms a separate layer from the initial layer. Addition of sulfuric acid (H2SO4) to
hydrolyze polysaccharide (amylum) and produce furfural. Because strong acids (H2SO4) cause hydrolysis of some polysaccharides and strong acids can react with a solution containing monosaccharides (sucrose and glucose) to produce furfural or its derivatives. When
sucrose
is
added
to
the
molisch
reaction,
the
sucrose is hydrolyzed by concentrated H2SO4 to appear in red sediment until finally dark purple. The dark purple color indicates that the trailer is a carbohydrate (positive test). Sucrose is a disaccharide of glucose and fructose When glucose is added to the molisch reaction, the mixture of glucose and the reaction of molisch (α-naftol) and reacted with concentrated H2SO4 will produce furfural hydroxymethyl until it forms a reddish-brown color first, eventually turning purple. Dark purple indicates that glucose is a monosaccharide-based carbohydrate (positive test). When amylum is added to the molisch reaction, the amylum and molish reaction (α-naftol) and reacted with concentrated H2SO4 will be hydrolyzed to appear red and eventually turn purple. Blackish purple indicates that amylum is a carbohydrate, a polysaccharide (positive test) Sucrose, glucose, and amylum showed a positive test with the addition
of
a
molisch
reaction
that
identified
all
three
as
carbohydrates. With the addition of concentrated H2SO4 will hydrolyze carbohydrates from the form of polysaccharides/disaccharides into monosaccharides. 2. Seliwanof Test a. Reaction In the test tube 1 (Amylum)
n + n H2O
H+
H+, O (can’t react)
2n
Resorsinol
Glucose In the test tube 2 (Lactose)
H2O, H+
H+, O (can’t react) Resorcinol
In the test tube 3 (Glucose)
H2O, H+
H+, O (can’t react) Resorcinol b. Explanation In this experiment there are 3 samples that will be tested seliwanof they are amylum, lactose, and glucose. The first step is to prepare the tools and materials needed, for the materials needed are seliwanoff, amylum, lactose, glucose, aquades, methylated reagents, while the tools that are needed are test tubes, pipettes, beaker , test tube racks. In the first experiment 5 drops of yellow wish seliwanof reagent solution were added then 5 drops of colorless amylum solution. Then shake it, then heat it in the water heated. Note the time needed to colour change. The solution does not change color. This indicates that amylum does not contain ketone groups, so they do not change color and give negative test results. In the second experiment 5 drops of yellow wish seliwanof reagent solution were added, and 5 drops of colorless lactose solution were added. Then shake the solution, then heated it in water bath. Note the time needed to colour change. The solution does not change. This indicates that glucose does not contain ketone groups, so it does not change color, and gives negative test results. The last, in the third experiment 5 drops of yellow wish seliwanof reagent solution were added, then 5 drops of colorless glucose solutin. Then shake the solution, then heat it in the heated. Note the time needed to colour change. The solution does not change. This indicates that glucose does not contain ketone groups, so it does not change color, and gives negative test results. 3. Barfoed Test a. Reaction Amylum
Glucose
Fructose
Sucrose
Cu(CH3COO)2 CH3COOH
Lactose
Cu(CH3COO)2 CH3COOH
(aq) b. Explanation After heating a dark blue solution was formed in each tube, and after heating> 10 minutes of starch and lactose did not form a brick red precipitate, but in glucose formed a brick red precipitate. This shows that glucose is a monosaccharide, where monosaccharides quickly reduce Cu (II) ions from Barfoed reagents to Cu (I). The red brick deposits formed are Cu2O deposits.
The principle is the reduction of Cu2 + found in barfoed reagents by the reducing group on monocasarida in acidic conditions. A positive reaction is indicated by the appearance of an orange-red or brick-red example. In the barfoed glucose test, fructose, lactose and sucrose react positively which is marked by the presence of red brick deposits after heating. So that glucose, fructose, lactose, and sucrose are reducing monosaccharide sugars as in the literature which states that the Bafoed test is used to test the presence of reducing monosaccharide sugars. 4. Tollens Test a. Reaction Making of tollens reagents:
2AgNO3 (aq) + 2NaOH (aq) → AgO (s) + 2NaNO3 (aq) + H2O (l)
Ag2O (s) + NH4OH (aq) → 2Ag(NH3)2OH (aq) + 3H2O (l)
Tollens test: The tollens test is positive if silver mirrors are formed which indicate the presence of reducing sugars Sucrose
+
(aq)
(aq) + 2Ag(NH3)2OH (aq) →
(aq) + 2Ag(s) silver mirror + NH3 (aq)
(aq) + 2Ag(NH3)2OH (aq) →
(aq) + 2Ag (s) silver mirror + NH3 (aq) Amylum
n (aq) + 2Ag(NH3)2OH (aq) Lactose
(aq)
(aq) +
2Ag(NH3)2OH (aq) + 2Ag (s) silver mirror + NH3 (aq) Glucose
(aq)
(aq) + 2Ag(NH3)2OH (aq) →
(aq) + 2Ag(s) silver mirror + NH3 (aq) Fructose
(aq) + 2Ag(NH3)2OH (aq) →
(aq) + 2Ag (s) silver mirror + NH3 (aq)
b. Explanation The fourth experiment is the tollens test. The purpose of the tollens test is to identify the presence of reducing sugars in carbohydrates. Aldehyde groups in all aldose species can be oxidized by weak oxidizing agents such as tollens (Hidajati, et al, 2019). The reduction from Ag + to Ag by reducing sugars is characterized by the formation of a silver mirror (Ag) and oxidizes the aldehyde group to the carboxylate group. A positive reaction by Tollens reagents is characterized by the formation of a silver mirror that shows a positive test for reducing sugars. Tests on Tollens reagents are based on the ease of aldehyde groups formed from reversible reactions of cyclic hemiasetal monosaccharides (Matsjeh et al, 1996). In the tollens test there are four carbohydrates to be tested, namely sucrose, starch, lactose and glucose. Each of these substances is inserted into each test tube. Test tube A contains sucrose, test tube B contains starch, test tube C contains lactose, and test tube D contains glucose. After that, each test tube drops 5 drops of tollens reagents that have been made earlier. Test tube A, the addition of a colorless solution tollens reagent to sucrose a colorless solution forming a silver mirror according to the theory shows that sucrose contains a reducing group. Sucrose is hydrolyzed into monosaccharides namely glucose and fructose. Tollens reagents will be reduced by monosaccharides both glucose and fructose from +1 to 0 so that the Ag deposits or commonly known as silver mirrors will be obtained.
Test Tube B, the addition of the colorless reagent tollens reagents to starch. The colorless solution is not formed silver mirror only brown solution, because starch has hemiasetal at one end of the molecule, but this end is only a small part of the whole starch molecule, so it does not affect the reaction. As a result, starch cannot reduce tollens reagents. This shows that starch is not a reducing sugar. Test tube C, the addition of the colorless reagent tollens reagent to the lactose of the colorless solution formed silver mirror according to the theory it shows that lactose is a reducing sugar. Lactose is hydrolyzed into monosaccharides namely glucose and galactose. Glucose and galactose which contain aldose groups and are reducing sugars can reduce Ag + charged + 1 from toll reagent to Ag neutral atom which has 0 charge to form silver mirror. Test Tube D, the addition of colorless solution tollens reagents to glucose colorless solution formed silver mirror according to the theory it shows that lactose is a reducing sugar. Glucose is a reducing sugar, glucose has an aldose group that can reduce Ag + from toll reagent reagents to Ag to form a silver mirror. Thus, substances containing reducing sugars are shown by the formation of silver mirrors namely glucose, sucrose, and lactose 5. Fehling Test a. Reaction Reaction of Fehling Test a. Lactose
+ 2Cu2+ + 5OH-
b. Sucrose
+ Cu2O + 3H2O
+ 2Cu2+ + 5OH-
↛
c. Glucose
+ Cu2O + 3H2O
+ 2Cu2+ + 5OH- d. Fructose OH
+ 2Cu2+ + 5OH-
+ Cu2O + 3H2O
e. Amylum
+ 2Cu2+ + 5OH-
↛
b. Explanation This experiment has the purpose to identify the presence of reducing sugar in the sample through the fehling test. This test is based on the reactivity of the substance to be oxidized against weak oxidizing agents. The principle of the fehling test is the ability of a sample containing reducing sugars to reduce a
fehling reagent containing Cu2+ ions to Cuions+ which is characterized by the formation of red brick deposits in the sample. Red brick deposits occur due to Cu2+ ions which are reduced by the aldehyde or ketone groups contained in the sample (Fessenden, 1992). Fehling reagents are made from a mixture of Fehling A and Fehling B. Fehling A (34.65 grams of copper sulfate in 500 ml of water) and Fehling B (a mixture of 173 grams of sodium hydroxisa and 125 grams of potassium sodium tartrate in 500 mL of water). The mixture of Fehling A solution and Fehling B solution is a blue solution (Sumardjo, 2009). The work step in this experiment is that 2 drops of sample are added with 2-3 ml of Fehling's solution. Then shake and heat it on a water bath for 3-4 minutes. In this experiment there were 4 samples, namely starch, lactose, sucrose and glucose in 4 different test tubes. a) Test tube 1. Starch 2 drops of colorless starch are put into a test tube and added with 2-3 ml of fehling solution. The solution will be blue. After it is shaken and heated, starch does not produce brick red deposits. This is because starch is not a reducing sugar. Although starch has an unsubstituted anomeric C atom at the end of the chain, the size of the starch molecule is not proportional to the size of Cu2+ (in the Fehling reagent), so the possibility of reaction is very small. So for the Fehling test on starch negative. b) Test tube 2. Lactose 2 drops of colorless lactose are inserted into the test tube and added with 2-3 ml of fehling solution. The solution will be blue. After being shaken and heated, lactose will produce brick red deposits. Deposition occurs because anomeric C atoms in lactose and glucose have not been substituted in the sense that OH groups bound to anomeric C atoms are still free to move from the alpha (α) to beta (β) position or the molecule undergoes mutarotation. When mutarotation occurs, the chain structure will open (previously closed). It is during this open chain that the Fehling reagent can oxidize the aldehyde group on the anomeric C atom. This is what causes the Fehling reagent to oxidize aldose groups in lactose and glucose
which is characterized by the formation of brick red deposits (Cu2O) which is the result of reduction of the Fehling reagent. So lactose is a reducing sugar. c) Test tube 3. Sucrose 2 drops of colorless sucrose are inserted into a test tube and added with 2-3 ml of fehling solution. The solution will be blue. After being shaken and heated, sucrose will not produce brick red deposits. Test results are negative. This shows that sucrose is not a reducing sugar. The size of the sucrose molecule is not proportional to the size of Cu2+ (in the Fehling reagent) so the possibility of reacting is very small. So that no red deposits are formed. d) Test tube 4. Glucose 2 drops of colorless glucose are inserted into a test tube and added with 23 ml of fehling solution. The solution will be blue. After being shaken and heated, glucose will produce brick red deposits. The aldehyde group contained in the sample when in water is in equilibrium with the open chain aldehyde form, so as to reduce Cu2+ ions by forming Cu2O compounds in the form of red deposits. Glucose is reducing sugar. 6. Sucrose hydrolysis a. Reaction Test tube 1
+
H+, OHSucrose Test tube 1A Glucose
Glucose
Fructose
(aq) + 2Cu2+ (aq) + 5OH-
(aq) + Cu2O
(s) + 3H2O Fructose
(aq) + 2Cu2+ 5OH-
(aq) + Cu2O (s)
+ 3H2O Test tube 1B 3H2O, H+
Cherry Red Test tube 2
H+, O, SO2
+
H+, OHSucrose
Glucose
Fructose
Test tube 2A Glucose
(aq) + 2Cu2+ (aq) + 5OH-
(aq) + Cu2O
(s)+ 3H2O Fructose
(aq) + 2Cu2+ 3H2O Test tube 2B
(aq) + Cu2O (s) +
H+, O, SO2
3H2O, H+
Cherry Red Test tube 3
+ H2O
Test tube 3A Benedict test
+ Cu22- (citrate)
Test tube 3B Seliwanoff test
H2 O
[H+]
b. Explanation Sucrose is a type of disaccharide carbohydrate consisting of two monosaccharides namely fructose and glucose. Both of them bind to C atom number 1 to glucose and number 2 to fructose to form a 1,2-βglycosidic linkage. The anomeric C atom in sucrose has been substituted so that it cannot reduce Benedict's reagent. However, in an acidic and warming atmosphere sucrose will be completely hydrolyzed or sugar inversion will form into glucose and fructose. So that the test with Benedict and seliwanoff will be positive, where Benedict's reagent will reduce glucose hydrolysis results and red brick deposits are produced. While the fructose seliwanof test results from hydrolysis will be detected to form a cherry red solution. While the success in addition to hot water will also experience a hydrolysis reaction, but the reaction is not as great as the addition of acids so that the hydrolysis reaction in the addition of hot water is a partial hydrolysis reaction. While the addition of cold water does not occur hydrolysis reaction. Hydrolysis of sucrose in addition to acids and heating, addition of hot water, and the addition of results obtained as follows: Compound
Sucrose
Addition
Reagent
Reagent
HCl + heating
Benedict
Seliwanoff
+
+
Hydrolysis occurs
+ = brick red precipitate (green solution) formed in benedict and cherry red solution formed in seliwanof - = no red brick deposits (green solution) were formed on benedict and not a cherry red solution formed in seliwanof.
In the results of experiments with the addition of acid followed by heating obtained positive tests with benedict and seliwanoff reagents which indicate that hydrolysis of sucrose to glucose and fructose occurs. This is in accordance with the theory. Compound
Addition Hot
Reagent
Reagent
water
Benedict
Seliwanoff
-
-
Partial Sucrose
hydrolysis occurred
+ = brick red precipitate (green solution) formed in benedict and cherry red solution formed in seliwanof - = no red brick deposits (green solution) were formed in the benedict and no red cherry solutions in the seliwanof form
In the results of experiments with the addition of hot water followed by heating obtained negative tests with benedict and seliwanoff reagents which indicate that there is no hydrolysis of sucrose to glucose and fructose. This is not in accordance with the theory. This is because the hydrolysis with hot water takes a long time so that it may take less time to warm up so that hydrolysis has not occurred. Compound
Sucrose
Addition
Reagent
Reagent
Cold water
Benedict
Seliwanoff
-
-
No hydrolysis occurs
+ = brick red precipitate (green solution) formed in benedict andncherry red solution formed in seliwanof - = no red brick deposits (green solution) were formed on benedict and not a cherry red solution formed in seliwanof
On the hypothesized experiment with the addition of cold water, negative tests were obtained with benedict and seliwanoff reagents which indicated that hydrolysis did not occur with sucrose to glucose
and fructose. This is consistent with the theory that the addition of cold water does not occur hydrolysis. 7. Pati Hydrolysis a. Reaction Test tube 1
n+ H+, OH-
Test tube 1A
+ I2
Test tube 1B
+ Cu2+ (aq) →
(aq) + Cu2O (s) + 3H2O (l)
Test tube 2
H2O
n+
Test tube 2A
+ n I2 →
n + 2 H2O (l)
Test tube 2B
n + Cu2+ (aq)
Test tube 3
H2O
n+
Test tube 3A
+ n I2 →
n + 2 H2O (l)
Test tube 3B
n + Cu2+ (aq) b. Explanation This experiment has purpose to produce glucose, maltose, dekstrin that test with iodin and benedict. To check polysaccharides in sample using iodine test, and to distinguish between aldose and ketose sugar in carbohydrates. The hydrolysis reaction of amylum involves water as a reductor. To observe the ongoing hydrolysis reaction can be tested with iodine. Iodine will react if the sample still contain amylum and cause the color of the solution to turn into blackish purple. To test the hydrolyzed amylum into glucose, benedict’s test can be performed, which show the sample turns blue and there is a red brick deposit at the bottom of the tube.
1) Test tube 1 First step is 2 ml of amylum solution added by 2 ml of HCl 3M. This way of addition concentrated acid is to hydrolyzed the amylum and also break the amylum’s structure because it has corrosive characteristic. Then steamed in the waterbath. After that cooled it down, continue with added 3 ml NaOH 3M, the result is colorless solution. The reaction is : Test tube 1
n+
H+, OH-
Then separate into 2 test tube with the same volume, which labelled by 1a and 1b, then test tube 1a added 1 drop of iodin which has brown colour, the result is the colour still colorless. It indicate that amylum was not hydrolized. This because iod reacts with basic solution so it does not reacts with amylum. This situation occurs because the presence of NaOH in the solution reacts with iod formed NaI and NaOI, so that in the test with the addition of NaOH, there is no change in the solution of amylum. The reaction is : Test tube 1A
+ I2 For test tube 1b, added by 3 drops of benedict reagent. The solution become electric blue solution. Next, heated it. The result is the formed brick red precipitate. This means, test tube 1b is perfectly-hydrolyzed. The reaction that occur is: Test tube 1B
+ Cu2+ (aq) →
(aq) + Cu2O (s) + 3H2O (l)
2) Test tube 2 For the second test tube, the first step is 2 ml of amylum solution added by 2 mL of aquadest then steamed for a while in the waterbath in order to hydrolyzed the amylum. After that cooled it down, then continue added 3 mL of aquadest again and separated into two different test tube with the same volume, which labelled by 2a and 2b. The reaction that occur is: Test tube 2
H2O
n+ For test tube 2a, added 1 drop of iodin which has brown colour, then the solution changed from colorless into dark-purple solution. The reaction that occurs is : Test tube 2A
+ n I2 →
n + 2 H2O (l) And for test tube 2b, added 1 mL of Benedict reagent then heated it. The solution become darker than before which is light blue solution and no precipitate formed. It indicate that there is no hydrolize process that occur. The reaction that occurs is :
Test tube 2B
n + Cu2+ (aq) 3) Test tube 3 For the third tube, the first step is 2 ml of amylum solution added by 2 mL aquades like test tube 2 but no heating process. Then, added again with 3 mL aquades and heated in the waterbath. The reaction that occurs is : Test tube 3 H2O
n+ Next, amylum solution after added aquadest divided into two different test tube with the same volume then labelled with 3a and 3b. For test tube 3a, added 1 drop of iodin which has brown colour, then the solution changed from colorless into dark-purple solution (++) solution. The reaction that occurs is : Test tube 3A
+ n I2 →
n + 2 H2O (l) But in test tube 3b, added by 1 mL of Benedict’s reagent, the solution become electric blue solution. Next, heated it. The result is there is no brick red precipitate formed. The reaction can write with : Test tube 3B
n + Cu2+ (aq)
Conclusion Based of the data experiment, it can concluded that: 1.
Molisch test aims to prove the existence of carbohydrates. The Molisch test shows that sucrose, glucose, and amylum are carbohydrates that indicate by forming purple colour
2.
Seliwanoff test aims to prove the existence of ketoses. Seliwanoff's test shows that in amylum, lactose and glucose there are no ketose groups that indicate by no colour changes
3.
Barfoed test aims to distinguish between monosaccharides and disaccharides. The Barfoed test shows that glucose and lactose is classified as monosaccharide, whereas amylum is disaccharides that indicate by forming red precipitate
4.
Tollens test aims to show the presence of reducing sugars in carbohydrates. From the Tollens test it can be concluded that sucrose, glucose, and lactose are reducing sugars that indicate by forming silver mirror
5.
Fehling test aims to determine the presence of aldose groups on carbohydrates, or test the presence of reducing sugars in carbohydrates. From the Fehling test it can be seen that lactose and glucose have aldose groups which can reduce fehling which is characterized by the formation of brick red deposits.
6.
To test the results of sucrose hydrolysis which is glucose and fructose, used benedict test or seliwanof test. The test show that tes tube 1 and 2 produce glucose and fructose which is indicated by the formation of brick red precipitate. A positive test in the seliwanoff test is indicated by the formation of an orange red color.
7.
The iodine test can be used to test the hydrolysis results in starch. The test show that tes tube 1 and 2 with iodine produce glucose and fructose which is indicated by the formation of dark blue solution, with formed light blue solution.
