The pea sized lump of fizzing sodium...
I recall a chemistry master trying to do exactly that. Unfortunately, while attempting to pare said pea-sized lump from a big stick of sodium, the stick slipped from his tongs and fell into said large glass trough.
We knew the loud bang was coming, the fact that his face went white and he hit the deck behind the bench while shouting "GET DOWN!" was a bit of a clue.
The trough was destroyed and the reinforced glass screen in a sturdy iron frame between us and it was pretty much buggered too.
Biting the hand that feeds IT
