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Why cant table sugar be the positive control in test using Benedict's solution?
Wiki User
∙ 12y ago
Table sugar, or sucrose, doesn't have an aldehyde group. Benedict's solution is used to determine if a reducing sugar is present. If it is a reducing sugar, the mixture will turn green/orange/red. The Benedict's solution contains copper (II) ions, which are reduced to a brick red precipitate of copper (I) oxide when the solution is heated. The Aldehyde (-CHO) group in a reducing sugar is the source of electrons that reduces copper (II) to copper (I). Since sucrose doesn't have an aldehyde group, it will not test positive for reducing sugars; it will not reduce the copper II in Benedict's to copper I and change the color of the solution.
Fructose does not have an aldehyde group, yet it is reducing, because it gets rearranged to the reducing glucose in basic solution.
All monosaccharides and some disaccharides are reducing sugars. Sucrose is one of the disaccharides that is not a reducing sugar.
Wiki User
∙ 12y ago
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Would raffinose react with benedicts reagent?
Benedicts reagent tests for reducing sugars, so the question is, is raffinose a reducing sugar. Raffinose is a trisaccharide made up of glucose, fructose and galactose. It is not a reducing sugar because all of its anomeric carbons are bonded, so it will not react with benedicts reagent.
If benedicts reagent turns red what substance is present?
the sugar glucose
Why did a solution of saliva and oats test positive with benedict's test and iodine test if the oats alone tested positive only in the iodine test and the saliva alone was negative for both?
polysaccharides and simple sugar
What indicator tests for sugar?
A simple test for testing sugar in a solution is by Benedict solution. Add Benedict solution to the solution on heat it will turn brick red or yellow depending upon its concentration.
Why does starch produce a negative result with Benedict's reagent?
Benedict test have a negative result in glycogen because glycogen is a polysaccharide. Benedict test is meant for testing reducing sugars. It can also give positive results in the case of disaccharide or monosaccharide.
What is the test for sugar using Benedicts solution?
prosrdure of benidect solution test
What is the stain solution when chemical is test for sugar?
It is normally benedicts solution. Add about 1/4 of the total sugar solution to a test tube and heat it in a hot water bath at around 50 degrees C for 5 min. For example, heat 40mL of sugar water (C12H22O11 aq ) with 10mL of Benedicts soluton (copper and sodium salts). If it is a positive test it will turn yellow.
Will hydrolysed dextrine give positive response to Benedict test?
Yes, it should. Benedicts test will be positive for reducing sugars, and since glucose is such a sugar, and would be a product of dextrin hydrolysis, you should get a positive result with Benedicts reagent.
What colour does Benedicts solution go with milk any kind of?
Yellow, because milk contains lactose which is a reducing sugar.
What is the indicator for carbohydrates?
Simple(sugar): benedicts solution. Turns bright orange. Complex(starch): iodine turns dark purple/black
Would glucose solution produce a positive Benedicts test?
No, Benedicts reagent will show positive results if the carbohydrate is a reducing sugar. You will know if it is positive if the sample will turn from blue to green then to orange when you are cooling the solution, which is the last step when you are performing the benedicts test for carbohydrates.
What is the positive reaction color for simple sugar?
The positive reaction color for simple sugar is orange, by Benedict's solution.
What chemical is used to test for reducing sugar?
Benedict's solution is used to test for reducing sugar.
What chemical is used to test for sugars?
Depends on the Sugar: Reducing sugars a normally monosaccharides but there are some disaccharides too like maltose. If its a reducing sugar then you would add Benedicts Reagent (alkaline copper(II) sulphate). You then heat it. if a reducing sugar is present then a precipitate is formed that will be red/orange. A Non-reducing sugar like Sucrose can be tested by first adding benedicts and heating. if no change is present you then add hydrochloric acid to hydrolyse the glycosidic bond. you then add a hydrogen carbonate solution to neutralise the acid. Then repeating the Benedicts and Heating process.
What does Benedicts plus sugar equal?
i need to kno what benidict plus sugar equals for biology
If corn oil is tested with Benedicts's solution and Biuret reagent and the final color is blue what do you know about corn oil?
Benedict's solution tests for aldehyde which is present in reducing sugars. If the solution remained blue than no reducing sugar's are present in corn oil.
Would raffinose react with benedicts reagent?
Benedicts reagent tests for reducing sugars, so the question is, is raffinose a reducing sugar. Raffinose is a trisaccharide made up of glucose, fructose and galactose. It is not a reducing sugar because all of its anomeric carbons are bonded, so it will not react with benedicts reagent.
