Which test result shows that a solution contains a reducing sugar?
Answer and explanation
Correct answer: D. An orange-red precipitate after heating with Benedict's solution
- Step 1: Reducing sugars reduce copper(II) ions in Benedict's reagent on heating. Step 2. This forms an orange-red precipitate of copper(I) oxide. Answer: An orange-red precipitate after heating with Benedict's solution. Why not the others: blue-black is the starch test; purple is the biuret test for protein; a white emulsion is the lipid test.
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