Tuesday, October 14, 2014

reducing sugar experiment

       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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