An organic compound yields a positive silver mirror test with Tollen's reagent but fails to produce — Practical Organic Chemistry and Purification Chemistry Question
Question
An organic compound yields a positive silver mirror test with Tollen's reagent but fails to produce a red precipitate when heated with Fehling's solution. Furthermore, it does NOT give a yellow precipitate with $I_2/NaOH$. Identify the compound.
💡 Solution & Explanation
The compound must be an aldehyde to give a positive Tollen's test. However, aromatic aldehydes like benzaldehyde cannot reduce the milder Fehling's solution. Acetaldehyde reduces both and also gives a positive iodoform test (yellow ppt of $CHI_3$). Formic acid reduces both Tollen's and Fehling's. Acetone is a ketone and fails Tollen's test. Thus, Benzaldehyde perfectly fits the criteria.