Question

By which of the following formic acid and formaldehyde can be distinguished?

• A. Benedict solution
• B. Fehling solution
• C. Tollen's reagent
• D. Sodium bicarbonate

Hint:

Tollen's reagent forms a silver mirror when it reacts with aldehydes like formaldehyde, which helps distinguish it from other compounds.

Answer 1

The Correct Option is C

Step 1: Understanding the reactions.
Formic acid and formaldehyde can be distinguished using Tollen's reagent. Tollen's reagent reacts with aldehydes to form a silver mirror, but does not react with formic acid, which is a carboxylic acid. Step 2: Analysis of options.
(A) Benedict solution: Benedict's solution is used to detect reducing sugars, not for distinguishing between formic acid and formaldehyde.
(B) Fehling solution: Fehling's solution is used for reducing sugars and aldehydes, but Tollen's reagent is more specific for distinguishing aldehydes like formaldehyde.
(C) Tollen's reagent: Correct — Tollen's reagent reacts with aldehydes like formaldehyde, forming a silver mirror, but does not react with formic acid.
(D) Sodium bicarbonate: Sodium bicarbonate is used to test for acids, but it does not specifically distinguish between formic acid and formaldehyde.
Step 3: Conclusion.
The correct answer is (C) because Tollen's reagent is used to distinguish between formic acid and formaldehyde.