BENEDICT'S TEST – REDUCING SUGARSBenedict's Test for Reducing Sugar results in color changes from blue precipitate to green and finally forms a brick red precipitate. In this case, Benedict's solution which is an aqueous solution of copper (II) sulfate, sodium carbonate and sodium citrate, is used as a test for the presence of reducing sugar. Glucose is one of the reducing sugars. The aldehyde (CHO) and keto (C=O) functional groups are found in glucose. The Benedict test will detect the aldehyde and keto functional group. As glucose has this functional group, the Benedict test shows positive results by changing the color of the Benedict reagent from blue to green to brick red precipitate. This test is therefore semi-quantitative. This is due to Benedict's reagent which reduces copper(II) sulfate by forming a precipitate of copper(I) oxide upon heating. The blue color means there is no reducing sugar, the green precipitate represents less sugar and the brick red precipitate means more sugars are formed. Therefore, the intensity of the color indicates the amount of sugar. Cu2+ (blue) ...