image by Flickr/Cyberchemist The Tollen’s Reagent is used to determine whether a solution contains an aldehyde or a ketone. Dilute sodium hydroxide is added to aqueous silver nitrate, this gives silver oxide, sodium nitrate and water. 2 AgNO3 (aq) + 2 NaOH (aq) → Ag2O (s) + 2 NaNO3 (aq) + H2O (l) Then, aqueous ammonia is added to the solution until it goes clear. This is due to the now silver ions existing as [Ag(NH3)2]+ complexes. Ag2O (s) + 4 NH3 (aq) + 2 NaNO3 (aq) + H2O (l) → 2 Ag(NH3)2NO3(aq) + 2 NaOH (aq) The silver precipitates out onto the inside of the container, giving the notable silver mirror as seen above.

image by Flickr/Cyberchemist

The Tollen’s Reagent is used to determine whether a solution contains an aldehyde or a ketone.

Dilute sodium hydroxide is added to aqueous silver nitrate, this gives silver oxide, sodium nitrate and water.

2 AgNO3 (aq) + 2 NaOH (aq) → Ag2O (s) + 2 NaNO3 (aq) + H2O (l)

Then, aqueous ammonia is added to the solution until it goes clear. This is due to the now silver ions existing as [Ag(NH3)2]+ complexes.

Ag2O (s) + 4 NH3 (aq) + 2 NaNO3 (aq) + H2O (l) → 2 Ag(NH3)2NO3(aq) + 2 NaOH (aq)

The silver precipitates out onto the inside of the container, giving the notable silver mirror as seen above.