Question

During a reaction of Tollen's test, the formation of mirror inside the tube is due to which of the following?

• A. Silver ions
• B. Silver atoms
• C. Silver compounds
• D. Silver nitrate

Answer 1

The correct option is B Silver atoms

Tollen's reagent oxidizes an aldehyde into the corresponding carboxylic acid.
$RCHO+2\left[Ag\right(N{H}_3{)}_2{]}^{+}+3O{H}^{-}\to RCO{O}^{-}+2Ag\downarrow +2H_{2}O+4N{H}_3\text{Aldehyde}\text{Tollen's Reagent}\text{Carboxylate ion}\text{Silver mirror}$
The reaction is accompanied by the reduction of silver ions in Tollen's reagent into metallic silver, which, if the test is carried out in a clean glass test tube, forms a mirror on the test tube. Thus correct option is (b).