video:lithium

4

Making absolute (water, oxygen and impurity free) ethylenediamine with lithium metal.

Alkali metals usually dissolve well in amines, the best example is lithium metal during Birch reduction that is dissolved in liquid ammonia. These solutions when dilute have usually a beautiful deep blue color due the solvated electrons. But if even traces of water or anything else is present what could react with the dissolved alkali metal, the color fades quickly. So till my highly impure ethylenediamine contains any water the deep blue color of the lithium metal is not visible, or fades quicky (first 3 gifs). On the last gif almost everything reacted from the amine, so the deep blue color remained in the flask. 

At the end I just had to distill the amine from the alkali metal under argon to keep the product pure enough for further purposes.