Tests for aldehydes & ketones Flashcards
1
Q
What is Tollens’ reagent?
A
Solution of silver nitrate in aqueous ammonia
2
Q
What ions does Tollens’ reagent contain?
A
Colourless silver(I) complex ions containing Ag+
3
Q
Write an equation to support a positive result with Tollens’ reagent
A
Ag+ + e- → Ag
4
Q
What is the positive result from Tollens’ reagent?
A
A silver mirror forms
5
Q
What is Fehling’s solution?
A
Copper(II) complex ion
6
Q
What does Fehling’s solution oxidise?
A
Only oxidises aldehydes but not ketones
7
Q
What is the positive result for Fehling’s test?
A
A brick red precipitate gradually forms
8
Q
Write an equation to support the positive result in the Fehling’s test
A
Cu2+ + 2e- → Cu+
9
Q
Give the full equation showing the complex ions for the silver mirror test with a positive result
A
[Ag(NH3)2]+ + e- → Ag + 2NH3
