Step 1: Understanding the Concept:
Specific chemical tests are used to identify the functional groups in carbohydrates. Aldoses (like glucose) contain an aldehyde group, while ketoses (like fructose) contain a ketone group.
Step 2: Detailed Explanation:
1. Seliwanoff’s Test: This test uses resorcinol and concentrated Hydrochloric acid (HCl).
2. Mechanism: When heated with HCl, ketoses dehydrate more rapidly than aldoses to form 5-hydroxymethylfurfural. This compound then reacts with resorcinol to produce a characteristic cherry-red color.
3. Others: Molisch test is a general test for all carbohydrates. Bial’s test is specific for pentoses. Benedict’s test detects reducing sugars.
Step 3: Final Answer:
Seliwanoff’s test is the standard diagnostic test used to differentiate ketoses from aldoses.