Preview

Lab Report: Reducing Sugars

Good Essays
Open Document
Open Document
606 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Lab Report: Reducing Sugars
In the previous lab we used different types of reagents to help determine if the presence of proteins, starches, and reducing sugars were present in the solutions we were provided with. The purpose of the lab was to allow us to have the opportunity to view the positive and negative reactions of the solutions we used, also to understand what that meant. The reagents we used allow us to detect whether or not there was a reducing sugar, starch, or protein present in the solutions. From what I knew previous to this experiment would be that if a substance contains a reducing sugar it will have a positive reaction, meaning the test tube should have either a slightly blue color or a red color to it. However, if the substance has a negative reaction …show more content…
Focusing on the reducing sugars part of this experiment, we gathered the substances that were presented to us into each individual test tube. One of these substances include lime soda, which is the substance that I am focusing on in this lab report. Once the test tube containing lime soda received two millimeters of Benedict’s solution we put it in a beaker full of water on top of a hot plate for three minutes. By heating the test tube for three minutes it allows us to view whether or not they are reducing sugars present in this substance. If there are reducing sugars detected then the test tube will have a positive reaction, thus granting us a color that should be either slightly blue or red. However, if there are no reducing sugars and there is a negative reaction, then the test tube will not undergo a color change. After we have completed this procedure we must record our results and analyze them.
In the result of the reducing sugars being present or not in lime soda, there was a positive reaction indicating that there was. After we put the two millimeters of the Benedict’s solution in into the test tube with lime soda the beginning color was blue. Once we placed the test tube into the beaker full of water and on top of the hot plate for three minutes it gradually started to change in its color. As a result, our test tube turned from a bright blue color into an orange and a slightly bluish color. After we recorded our results we began to analyze them and discuss as a group on what had

You May Also Find These Documents Helpful

  • Good Essays

    Biology 130l Exam Review

    • 2549 Words
    • 11 Pages

    The terminal aldehyde group makes it an aldose sugar, which reacts in Benedict's test to make glucose a reducing sugar. Blue solution will develop precipitate ranging from yellow, green, red or brown (positive).…

    • 2549 Words
    • 11 Pages
    Good Essays
  • Powerful Essays

    The point of this lab is to determine if a substance contains carbohydrates such as a reducing sugar and/or polysaccharides. This will be done by using Benedict’s reagent and Iodine stain tests. Benedict’s reagent will react to reducing substances in the solution by oxidizing it and changing the structure of the reducing sugar to form a colored precipitate. The color of this precipitate can be used to determine the concentration of reducing sugars in the substance. If the precipitate is blue no reducing sugars are in the substance. If the precipitate is bluish green, green, yellow, or orange it does contain reducing sugars. Iodine stain will be used to determine if the solution contains polysaccharides.…

    • 1115 Words
    • 5 Pages
    Powerful Essays
  • Satisfactory Essays

    Review Sheet 39b

    • 603 Words
    • 3 Pages

    We used a negative control to see if there is any amylase in the maltose…

    • 603 Words
    • 3 Pages
    Satisfactory Essays
  • Satisfactory Essays

    * When the solution was added to the hot water bath, the solution went from blue, to green, to yellow, and finally to orange as time progressed. This was a positive result, meaning that the amylase in our saliva broke the polysaccharides in the cracker into mono- and di- saccharides. As a result, the Benedict’s reagent changed colour because it indicated the presence of mono- and di- saccharides in the solution.…

    • 433 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    Simple Sugar Lab

    • 608 Words
    • 7 Pages

    Benedicts solution is a chemical solution that changes color in the presence of glucose and…

    • 608 Words
    • 7 Pages
    Good Essays
  • Satisfactory Essays

    Bio Lab

    • 549 Words
    • 3 Pages

    While waiting, my lab group and I came up with a hypothesis. We hypothesized that if we were to add salivary amylase to the saltine cracker it would start to digest/break down. We made this hypothesis because by going back to the data table from part I, we knew that saltine crackers had starch because it tested positive. In addition, from previous science classes we had been aware of the enzyme of salivary amylase, so the hypothesis came with relative ease as we were all confident in our hypothesis. After testing the hypothesis by removing the beakers carefully out of the water bath and observing the color, our hypothesis was correct. This is because the indicator that we used to test for sugar (Benedict’s Solution) came out of the water bath a blackish color. Meaning that a quantity of the starch had been chemically broken down into sugars, thanks to the salivary amylase. We knew that there was sugar in the content because if the indicator shows any color other than blue, that means that the substance being tested has sugar presence contained in it.…

    • 549 Words
    • 3 Pages
    Satisfactory Essays
  • Powerful Essays

    Benedict 's solution contains Cu+2 ions that are blue in colour. This means that when Benedict 's solution is added to clear transparent or translucent solutions, the solutions turn light blue due to the presence of the Cu+2 ions. Out of the 12 solutions, solution 10 (beer) was a light brown-yellow colour, while the remaining 11 were either transparent or translucent. Thus, when Benedict 's solution was added to solution 10 (beer), it turned blue-green. It then turned into a thick pale yellow colour indicating that a reaction had taken place and it was positive. This is because although solution 10 (beer) did not turn red-brown, there was a colour change and a coloured precipitate was formed. After adding the Benedict 's solution to the remaining 11 solutions, the test tubes were put into a beaker on a hot plate and were left to boil for about 5 minutes. Five of the solutions changed from a light blue colour to different shades of red-brown. When Benedict 's solution is added to reducing sugars, the Cu+2 ions for a red-brown precipitate of Copper (I) Oxide causing all sugar solutions to turn red-brown (Hunt, n.d.). Solution 1 (1% glucose solution) turned light red-brown, solution 3 (1% maltose solution) turned red-brown, solution 4 (honey solution) turned brown almost instantly, solution 6 (1% lactose solution) turned red, and solution 12 (unknown 318) turned red orange. This indicated that…

    • 2377 Words
    • 10 Pages
    Powerful Essays
  • Satisfactory Essays

    Carbohydrate and Points

    • 614 Words
    • 3 Pages

    2.List whether each of the following substances was positive or negative for reducing sugar, as indicated by the Benedict's test. (6 points)…

    • 614 Words
    • 3 Pages
    Satisfactory Essays
  • Good Essays

    A few experiments were performed to test for the presence of the different types of macromolecules of various solutions. The iodine tested for starch and glycogen, Benedict’s test tested for reducing sugars for carbohydrates and biuret test was performed to test for proteins. It is necessary to understand how important controls are in a lab experiment. A control is where all of the experimental variables can be controlled and monitored. Results are determined by comparing these variables to the control. Without them, no results would be valid in the experiment. To tell whether or not the experimental procedure were carried out properly and correctly, treatment controls were used. They can either be positive or negative. Correct data with followed procedures, resulting in a working experiment would be a positive control. On the opposite hand, negative controls would give negative results if everything were to be followed in the experiment.…

    • 1158 Words
    • 5 Pages
    Good Essays
  • Good Essays

    Nutriton lab

    • 851 Words
    • 3 Pages

    1a) In a positive test for sugar, one would see the colour of the substance change from blue to light green to greenish yellow to orange and lastly reddish brown.…

    • 851 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Hydrogen and Points

    • 968 Words
    • 4 Pages

    1. List whether each of the following substances was positive or negative for reducing sugar, as indicated by the Benedict's test. (6 points)…

    • 968 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Firstly, a source of error may occur during the Benedict 's test. Positive results may occur when their should not be. This is due to the fact that there may be a presence of another substance that can be oxidized other than reducing sugars. Furthermore, another source of error may be the dirty test tubes which may sway some reactions when solutions are mixed. Measurements may be another source of error. Such as using a plastic measuring cup can measure off by +/- 5%, and estimating the amount of solution in half a pipette. To improve this lab, and the Benedict test, another test should be done for non-reducing sugars that may give positive results. Another way to improve the lab is to use distilled water as a solution for comparision. The distilled water will not result in a positive control in the test due to the fact that water does not contain any macromolecules. The water can be compared with other solutions for a negative control. The results for iodine test indicate that solutions 1,2,3,4,5,6,9,10 and 11 turn yellow when mixed with iodine and therefore the solutions do not contain starch or glycogen. The yellow is a result from a colorless solution mixed with iodine. Solutions 7 and 12 turned red/brown when iodine was added. Conclusions can be made that these solutions contain glycogen. The highly branched structure reacting with iodine and gives it that red/brown color. Furthermore, solution 8 turned blue/purple which is an indication that it is starch, and it was also expected to result positive because it was 1% starch solution. Solution 7 therefore contains amylose and amyloepectin. But it is the amylose that initially reacts with iodine creating a blue color. Secondly, the results for the Benedicts test showed that solutions 2, 5, 7, 8, 9, 11 and 12 had a negative control. No color change. Therefore these solutions do not contain any molecules that can reduce cupic ions such as a reducing sugar. An…

    • 1411 Words
    • 6 Pages
    Good Essays
  • Better Essays

    For the firsts three sets of titration trials of baking soda powder was used. About 0.3 grams of baking soda powder were measured and mixed with 20mL of deionized water in a beaker. Three drops of the indicator bromothymol blue were put in the baking soda solution and mixed well. A burette and funnel were rinsed off using water and cleaned well. The burette and funnel were rinsed a second time using 5mL of the HCl solution that was prepared the previous week and disposed of in a clean beaker. The rest of the HCl solution was then put in the burette. The beaker containing the baking soda solution was placed under the burette. 1mL of the HCl solution was released at a time into the beaker with the baking soda until a change was observed. The results were recorded. The process was repeated three more times and the results were recorded. For the second sets of titration trails, fresh squeezed lemon juice was used. 5mL of lemon juice were used and three drops of the indicator phenolphthalein were put in the juice. The burette was then rinsed off with water and rinsed off a second time using NaOH and disposed of in a clean beaker. The rest of the NaOH solution was put in the burette and the beaker containing the lemon juice was placed under the burette. 1mL of the NaOH solution were released at a time into the beaker containing the lemon juice until changes were observed. The results were…

    • 1661 Words
    • 7 Pages
    Better Essays
  • Satisfactory Essays

    Sugar Study

    • 277 Words
    • 2 Pages

    Research on how sugar affects kids could be used by either the experimental method, or by the…

    • 277 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Chemistry Lab Questions

    • 941 Words
    • 4 Pages

    2. List whether each of the following substances was positive or negative for reducing sugar, as indicated by the Benedict's test. (6 points)…

    • 941 Words
    • 4 Pages
    Satisfactory Essays