Final answer:
Tollens' reagent is made by dissolving silver nitrate in distilled water and adding ammonia. To test for the aldehyde group in cinnamaldehyde, the test compound is mixed with Tollens' reagent and heated. An aldehyde will form a silver mirror as the organic product of the reaction.
Step-by-step explanation:
Tollens' reagent is a commonly used reagent to identify the presence of an aldehyde group in compounds such as cinnamaldehyde. It is made by dissolving silver nitrate (AgNO3) in distilled water and adding a few drops of concentrated ammonia solution (NH3) until a brown precipitate of silver oxide (Ag2O) is formed.
The precipitate is then dissolved by adding a small amount of dilute ammonia solution. The resulting clear solution is Tollens' reagent. To carry out the test, a small amount of the test compound, like cinnamaldehyde, is mixed with Tollens' reagent in a test tube.
The test tube is heated gently by placing it in a water bath. If the test compound is an aldehyde, it will react with Tollens' reagent and form a silver mirror on the inner surface of the test tube. This silver mirror is the organic product of the reaction.