JEE MainChemistryAldehydes and Ketones
Which of the following pairs of compounds can be distinguished by using ammoniacal silver nitrate solution?
Options
- AAcetaldehyde and Benzaldehyde
- BFormic acid and Acetic acid
- CFormaldehyde and Formic acid
- DAcetone and Benzophenone
Correct answer
B. Formic acid and Acetic acid
Step-by-step solution
To distinguish a pair of compounds using a specific reagent, one compound must give a positive test while the other gives a negative test. Ammoniacal silver nitrate (Tollens' reagent) is a mild oxidizing agent that oxidizes aldehydes and formic acid, resulting in a silver mirror. Let us evaluate each pair: 1) Acetaldehyde (aliphatic aldehyde) and Benzaldehyde (aromatic aldehyde): Both give a positive Tollens' test. Cannot be distinguished. 2) Formic acid and Acetic acid: Formic acid contains an aldehydic hydrogen a