I.
Introduction
A. Aim
To testing out
reducing sugar presence or not in a sample by using the benedict’s solution
B.
Background
theory
Sugar has important
role for our body and it has many types of it like non-reducing sugar and
reducing sugar. Sugar is important as the main energy of our body in a form of
ATP (more explanation on cellular respiration) that our organs can use to run
its function. By this experiment, benedict’s solution is used as the indicator
whether the sample is containing reducing sugar or not
C. Hypothesis
If I put the indicator which is benedict’s solution, then the
sample will change its color because the reducing sugar will react with the benedict’s
solution. If there is no reducing sugar in the sample, then there will be no
changing of color in the sample.
II.
Methodology
A. Materials
1.
Test tube rack
2.
5 test tubes
3.
Pipette
4.
Burner
5.
Water
6.
Glucose
7.
Sucrose
8.
Starch
9.
Beaker
10.
Tripod
11.
0.1M HCl
12.
0.1M NaOH
13.
Benedict’s solution
14.
Conical flask
B. Method
i.
Non-Hydrolyze
solution (sucrose, glucose, starch, water)
1.
Take 5 mL of sample to the test tube
2.
Put 10 drops of benedict’s solution using the
pipette (the solution’s color will be blue)
3.
Boil the solution by put the test tube into a
beaker that full of boiling water for 10 minutes
4.
Take the test tube away from the beaker and
observe the color of the solution
ii.
Hydrolyze
solution (sucrose)
1.
Take 5 mL of sucrose to the test tube using the
conical flask
2.
Put 5 drops of 0.1 HCl
3.
Put the test tube into boiling water for 5 min
4.
Put 2 mL and 10 drops of benedict’s solution to
the test tube (the solution’s color will be blue)
5.
One more time put the test tube into boiling
water for 10 min
6.
Take away the test tube and observe the color
III.
Result
Sample
|
Result/observation after heating
|
Is it reducing sugar?
|
Glucose
|
Brick Red
|
Yes, very strong one
|
Starch
|
Green
|
Yes, a weak
one
|
Water
|
Blue
|
No
|
Non-hydrolyzed sucrose
|
Orange
|
Yes, a
moderate one
|
Hydrolyzed sucrose
|
Green
|
Yes, a weak one
|
IV.
Analysis & discussion
If the color is
changed from blue, we can conclude that the solution is containing reducing
sugar in it. The order of colors from the weakest reducing sugar to the
strongest one is blue, green, yellow, orange and brick red.
The hydrolysis
process has a very important role to identify the reducing sugar. If we look at
sucrose, the reducing sugar presence in non-hydrolyzed sugar is stronger than
the hydrolyzed sucrose. This happens because the hydrolysis process breaks down
the glycosidic bond of sucrose and it reacts before we test it by using the
benedict’s solution, resulting that the hydrolyzed sucrose contain less
reducing sugar
V.
Conclusion & recommendation
My conclusion for
this experiment is that based on my data, glucose is the sweetest carbohydrates
because it contains a huge amount of reducing sugar. My hypothesis and my
observation data is match because the sample that have the reducing sugar will
react with benedict’s solution by changing its color. While the sample that has
no reducing sugar (water), does not change its color.
My recommendation
for error in this experiment is when you read the volume of the sample. Make sure
that you take an exactly 5mL of sample and read it in the eye level. The other
source of error in this experiment is the time taken for boiling the substance
in water. Make sure you have stopwatch to make sure that it heated for 10
minutes in the boiling water
VI.
Reference list
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