page_title: Tollens' reagent
hierarchical_section_title: Tollens' reagent
caption_attribution_description: English: Tollens test Deutsch: Tollensprobe
context_page_description: Tollens' reagent is a chemical reagent used to determine the presence of aldehyde and aromatic aldehyde functional groups along with some alpha-hydroxy ketone which can tautomerize into aldehyde. The reagent consists of a solution of silver nitrate, ammonia and some sodium hydroxide. It was named after its discoverer, the German chemist Bernhard Tollens. A positive test with Tollens' reagent is indicated by the precipitation of elemental silver, often producing a characteristic "silver mirror" on the inner surface of the reaction vessel.
context_section_description: Tollens' reagent  is a chemical reagent used to determine the presence of aldehyde and aromatic aldehyde functional groups along with some alpha-hydroxy ketone which can tautomerize into aldehyde. The reagent consists of a solution of silver nitrate, ammonia and some sodium hydroxide (to maintain a basic pH of the reagent solution). It was named after its discoverer, the German chemist Bernhard Tollens.  A positive test with Tollens' reagent is indicated by the precipitation of elemental silver, often producing a characteristic "silver mirror" on the inner surface of the reaction vessel.
caption: Tollens' test for aldehyde: left side positive (silver mirror), right side negative
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