A sugar solution was boiled with fehling’s solution A and B and the colour remained blue. The sugar tested was
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Correct Answer: Option D
Explanation:
Fehling’s solution is used to test for the presence of reducing sugars. It contains copper(II) ions, which are reduced to copper(I) oxide (a red precipitate) in the presence of reducing sugars.
Since sucrose is a non-reducing sugar, it does not react with Fehling's solution. The blue color remains unchanged because sucrose does not reduce the copper(II) ions in Fehling's solution.
Quick explanation for the others:
A. Glucose – A reducing sugar, which would turn the solution from blue to a red precipitate.
B. Maltose – A reducing sugar, would also react and change the color.
C. Fructose – A reducing sugar, would similarly change the color.
E. Lactose – A reducing sugar, would cause a color change as well.
Fehling’s solution is used to test for the presence of reducing sugars. It contains copper(II) ions, which are reduced to copper(I) oxide (a red precipitate) in the presence of reducing sugars.
Since sucrose is a non-reducing sugar, it does not react with Fehling's solution. The blue color remains unchanged because sucrose does not reduce the copper(II) ions in Fehling's solution.
Quick explanation for the others:
A. Glucose – A reducing sugar, which would turn the solution from blue to a red precipitate.
B. Maltose – A reducing sugar, would also react and change the color.
C. Fructose – A reducing sugar, would similarly change the color.
E. Lactose – A reducing sugar, would cause a color change as well.