Benedict's reagent is used for detecting reducing sugars because _________.
the —OH groups are exchanged for hydrogens.
the copper ion in the reagent is oxidized as the sugar is reduced.
the aldehyde group in the sugar is oxidized.
a reduction of the sugar occurs producing an acid.
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The correct answer is: the aldehyde group in the sugar is oxidized.
Benedict's reagent is a chemical solution that contains copper ions (Cu2+). It is used to test for the presence of reducing sugars, which include monosaccharides (such as glucose and fructose) and some disaccharides (such as maltose and lactose).
In Benedict's test, the aldehyde group (-CHO) in a reducing sugar gets oxidized in the presence of the copper ions. The copper ions are reduced from Cu2+ to Cu+ as a result of this oxidation process. This reduction of copper ions is visible as a color change, producing a red precipitate or a color spectrum ranging from green to yellow to red, depending on the amount of reducing sugar present.
Therefore, the correct statement is that the aldehyde group in the sugar is oxidized, leading to the detection of reducing sugars using Benedict's reagent.