Procedure 3 :- Take a water bath but if not available the take a 400 ml beaker and add 200 ml water into it and place the beaker on a hotplate which is in contact with heat.This will work as a water bath. Take 4 test tubes and number them 1,2,3,4.Now add 2 ml of 1% starch solution into test tube 1,2 ml of 0.1M glucose solution into test tube 2, 2 ml of 0.1M galactose solution into test tube 3, 2 ml of unknown solution into test tube 4.Then add 2 ml of Benedict's reagent into each test tube and mix well.After mixing place those test tubes in boiling water bath for 3 minutes.At last remove these test tubes from water bath, observe the change then record the result.
S.No. | sample solution (2ml) | Benedict's reagents | Result | |
Test tube 1 | 1% starch | 2 ml | -ve | |
Test tube 2 | 0.1M glucose | 2 ml | +ve | |
Test tube 3 | 0.1M galactose | 2 ml | +ve | |
Test tube 4 | unknown | 2 ml |
Depends on type of sugar |
Benedict's test is used for the detection of reducing sugar within the solution.Reducing sugar act as a reducing agent because they have free aldehyding and ketonic group.
Benedict's reagent = Copper (II) sulphate (CuSO4 5H2O) + sodium citrate + sodium carbonate (Na2CO3).It is blue in colour,if there is any reducing sugar within the solution then on addition of this reagent there will be change in the solution colour on heating or appearence of red precipitate with in the solution. This indicate the presence of reducing sugar and the result for this test is positive.
Starch does not give this test because glucose units are connected by 1-4 glycosidic bond.Starch will give +ve result on on hydrolysis.Both glucose and galactose are reducing sugar so both give + ve Benedict's test.Unknown solution reducing solution result will depends upon the type os sugar.
Can someone help me rewrite procedure #3 in paragraph notation. It should be written so that...
QUESTION: Write a flow scheme for the work-up. THE WORK UP: C. Work-up (save all layers) and Isolation of Product MgBrCl Benzoic acid Transfer the mixture into a test tube. Rinse the beaker with about 3 mL of regular (not anhydrous) diethyl ether and pour the washings into the test tube. There should be two distinct layers in the test tube Remove the aqueous layer (to be discarded) and shake the ether layer with about 2 mL of 3 M...
Need help filling in the chart and answering the questions that go along with it. I have added the procedure and the instructions as well as the "results" that are supposed to be used to fill in the chart. Thank you! We were unable to transcribe this imageTABLE 8-1 Cast of Characters and a Legend of Abbreviations Name Symbol Function in This Experiment Green fluorescent protein GFP It serves as an indicator of successful transformation and gene transcription expression in...
PROCEDURE 1. Place a reaction tube into a 5-mL Erienmeyer and tare. Add between 0.275- 0.300g of salicylic acid. Record on the data sheet. 2. Transfer the reaction tube and 5-ml Erienmeyer to the hood. Add a boiling chip, 2 drops of 85% phosphoric acid, and about 0.70 mL of acetic anhydride to the reaction tube. Mix well. 3. Place a 50-ml beaker containing about 20-mls of water on a hot plate or in the sand bath. Allow the water...
2130 D. HYDROLYSIS OF DISACCHARIDES and POLYSACOLARIDES Make sure you understand what you are doing bore Both the lodine Test and Benedict's best becau described below. Label test tubes so they are t s See the datatable for any that you pre heated in a hot waterbuch e e h 1. You will need 4 test tubes, 1 and 2 forstarch and dowe l of such to test tubes 1 and 2 Add a small pinch of sucrose to test...
can someone please answer number one? im so lost DYES AND DYEING CHAPTER 1. Calculate the amounts of salicylic acid, 1-naphthol, 2-naphthol, 8-anilino-1-naph- thalenesulfonic acid ammonium salt, or N,N-dimethylaniline needed for Part 1B of this experiment (use molecules as assigned by your TA). 190mg 3-aminobenzene 2.5mL Sulfonic acid 2.5% sodium carbonate solution 81mg Sodium nitrate 2. What is the purpose of the sodium carbonate in Part 1A? Why do we add glacial acetic acid in Part 13 when we react...
Questions: 1. What is responsible for a positive Benedict's test? 12-KI test? 2. What is responsible for a positive Biuret test? How are lipids detected? 3. Which biomolecules are present in the food samples? Procedure: Benedict's test 1. Fill 100 mL Beaker with 40 mL of water. 2. Place the burner stand over the burner and light it up using a match. 3. Place the beaker containing water over the burner stand to make a water bath. 4. Label 3...
Write out your separation scheme for this experiment. 1. Heat 75 mL of water to 90 °C in a 250-mL beaker. 2. While the water is being heated, place 250 mg of salicylic acid, 1 drop of 85% phosphoric acid and 0.5 mL of acetic anhydride in a test tube. Add a boiling chip to the mixture and gently shake it in order to mix the reactants. 3. Heat the tube in the beaker of water at 85 - 90...
Proteins are composed of amino acid units bound by peptide bonds. By the addition of the enzyme Bacterial Protease these bonds are broken and the individual amino acids are freed. A simple test for free amino acids is the use of the reagent Ninhydrin which turns purple in the presence of amino acids but remains yellowish in the presence of protein. I. Label one 250 ml beaker A and one 250 ml beaker B. To each beaker add l 00...
please help asap and the values are from the procedure there is no additional info QUESTION. PROCEDURE 1. Obtain seven spectrophotometer tubes, three 5 mL pipets and seven 125 mL Erlenmeyer flasks. One for the blank and six sample test tubes. Make sure to label the test tubes with appropriated calculated concentration. Label one flask as NaSCN 2. Pipet 5 mL of 0.00020 M NaSCN into Erlenmeyer flask #1. Pipet 5 mL of 0.20 M Fe(NO3)3 into Erlenmeyer flask #1....
Can someone help me with the color reactions, positive and negative control, and the 6 questions? Sudan IV Test for Lipid 1. Obtain five test tubes and number them 1-5. Your instructor may ask you to test some additional materials. If so, include additional numbered test tubes. 2. To each tube, add the materials listed in Table 3. 3. Add five drops of water to tube 1 and five drops of Sudan IV to each of the remaining tubes. Mix...