No, starch does not reduce Fehling's solution. Starch is a polysaccharide composed of glucose molecules linked together, whereas Fehling's solution is a complex of copper sulfate, sodium hydroxide, and potassium sodium tartrate used to test for the presence of reducing sugars. Starch is not a reducing sugar and therefore will not react with Fehling's solution.
I think you are referring to the test using Fehlings solution. Fehlings solution oxidises aldehydes and ketones and formic acid and is in turn reduced. The red precipitate is the copper(I) oxide formed by reduction of the copper(II) complex found in Fehlings solution. Acetic acid is not readily oxidised and so there is no precipitate. See link for more information on what the complex is in Fehlings solution and how it is prepared.
Fehling's A solution is blue in color due to the presence of copper sulfate.
Fehling's solution is originally blue in color due to the presence of copper ions.
Starch is not a solution.
The organic compound that reacts with iodine in a starch solution is amylose, which is a polysaccharide and a component of starch. When iodine is added to a starch solution, it forms a blue-black complex with the amylose present in the solution.
I think you are referring to the test using Fehlings solution. Fehlings solution oxidises aldehydes and ketones and formic acid and is in turn reduced. The red precipitate is the copper(I) oxide formed by reduction of the copper(II) complex found in Fehlings solution. Acetic acid is not readily oxidised and so there is no precipitate. See link for more information on what the complex is in Fehlings solution and how it is prepared.
Fehling's A solution is blue in color due to the presence of copper sulfate.
Fehling's solution is originally blue in color due to the presence of copper ions.
Starch is not a solution.
The organic compound that reacts with iodine in a starch solution is amylose, which is a polysaccharide and a component of starch. When iodine is added to a starch solution, it forms a blue-black complex with the amylose present in the solution.
The Fehling A solution contain copper sulfate.The Fehling B solution contain sodium potassium tartrate and sodium hydroxide.
IKI solution is used to test for the presence of starch. Starch will turn blue-black in the presence of IKI solution, indicating a positive test result for the presence of starch.
The chemical is called Iodine solution. If starch is present, the iodine solution will turn from amber to blue black.
Starch indicator solution will remain its original color (usually colorless) in the absence of starch. Without starch present, there will be no color change observed when using starch indicator solution.
Starch powder turns blue-black in iodine solution due to the formation of a starch-iodine complex.
Iodine solution is a brownish liquid used to test for the presence of starch, turning blue-black in the presence of starch. Starch solution, on the other hand, is a clear liquid made by dissolving starch in water.
The iodine will turn the starch solution blue-black due to the formation of a starch-iodine complex. If the starch solution also contains vitamin C, the vitamin C may react with the iodine, preventing the blue-black color change from occurring. This is because vitamin C is a reducing agent and can reduce iodine back to its colorless form.