Aldehydes And Ketones

Step 1: Fehling’s solution reaction. Fehling’s solution is a mixture of copper sulfate and alkali used to test for aldehydes. Formic acid (a form of aldehyde) reduces Fehling’s solution, while other acids do not.
Step 2: Conclusion. Thus, formic acid reduces Fehling’s solution.

Step 1: Understand the reaction with concentrated H SO . Acetaldehyde, when reacted with concentrated sulfuric acid, undergoes dehydration and polymerization, ultimately forming a black residue.
Step 2: Conclusion. Thus, acetaldehyde is charred to a black residue when treated with concentrated sulfuric acid.

Step 1: Understanding Rosenmund reaction.
In the Rosenmund reduction, an acyl chloride is reduced to an aldehyde using palladium on barium sulfate (Pd / BaSO₄) as a catalyst.

Step 2: Conclusion.
Thus, the correct catalyst is option (B).

Final Answer:

Step 1: Hydrogenation reaction.
When aromatic aldehydes like benzaldehyde react with ammonia in the presence of hydrogen and nickel, they undergo reduction to form the corresponding amine. In this case, the product formed is phenylethylamine.

Step 2: Conclusion.
Thus, the correct product is phenylethylamine , so the correct answer is option (C).

Final Answer:

Step 1: Understand Cannizzaro reaction.
The Cannizzaro reaction involves the base-induced disproportionation of non-enolizable aldehydes, which results in the formation of an alcohol and an acid.
Step 2: Conclusion.
The aldehyde undergoes the Cannizzaro reaction.
Final Answer:

The reactivity of carbonyl compounds with Grignard’s reagent depends on the steric and electronic factors. Compound I is more reactive due to the less hindered carbonyl group.

Tollen's test is positive for aldehydes and reducing sugars. Glucose and fructose are reducing sugars, so they will give a positive result.

Step 1: Understanding the Reaction.
Acetophenone and benzophenone can be distinguished by the Canizzaro’s reaction, where aldehydes without an alpha-hydrogen undergo disproportionation to form an alcohol and an acid.
Step 2: Conclusion.
The correct answer is (B), Canizzaro’s reaction.

Step 1: Ketal Formation.
Ketal formation occurs when a glycol reacts with an aldehyde or ketone. The reaction between glycol and acetone forms a ketal.
Step 2: Conclusion.
The correct answer is (A), Glycol with acetone.

Step 1: Understand the reaction.
When benzaldehyde and formaldehyde are heated with aqueous NaOH, they undergo the benzoin condensation, forming sodium benzoate and sodium formate.
Step 2: Conclusion.
Thus, the products are sodium benzoate and sodium formate.
Final Answer:

Step 1: Understand the aldol condensation.
Aldol reaction is the condensation between two carbonyl compounds. The reaction given shows the condensation of 5 molecules of acetaldehyde.
Step 2: Conclusion.
Thus, the number of aldol reactions is 3.
Final Answer:

Step 1: Understand the reaction mechanism.
In the reaction of benzaldehyde with methanol, the intermediate is formed by protonation and nucleophilic attack, but is not an intermediate in this reaction.
Step 2: Conclusion.
Thus, the intermediate that is not involved is .
Final Answer:

Step 1: 2,4-Dinitrophenylhydrazine reacts with carbonyl compounds to form hydrazones. This reagent can distinguish acetophenone from benzophenone.
Step 2: Acetophenone reacts to form a hydrazone, whereas benzophenone does not.

Final Answer:

The compound A reacts with iodoform reagent to give a yellow precipitate, confirming the presence of a methyl ketone group. Propanone undergoes this reaction to form mesityl oxide.
Final Answer:

Tautomerism is a form of isomerism where two isomers can interconvert through the transfer of a proton or rearrangement of electrons, typically in compounds with a keto-enol type relationship.
Final Answer: