Transition metal ion and alkali reactions

A good starting point would be to review the properties of the transition elements. In these simple test tube experiments we shall react seven cations with sodium hydroxide solution and also with ammonia solution. The results of these reactions can be used to identify unknown cations.

It is useful to remember that ammonia solution is alkaline due to the following equilibrium:

NH₃(aq) + H₂O(l) NH₄⁺(aq) + OH^-(aq)

Consequently, we may find similar reactions with sodium hydroxide and ammonia (the formation of an insoluble hydroxide is the most common result). Ammonia can also form a complex ion with the transition metal cation, so in some cases the reactions differ.

Watch the videos and make notes of your observations. Try to write equations for the reactions you see.

Video - the reactions with sodium hydroxide solution

Video - the reactions with ammonia solution

Results - transition metal ion reactions