Explosion inside a glovebox
It is possible to have an explosion inside a nitrogen-filled glovebox.
Alkali metals such as lithium, sodium, potassium will react with Teflon even under inert atmosphere. You might think Teflon is bullet proof. I had one incident when an egg-shaped stir bar was dropped to a sodium-potassium (NaK) alloy in an nitrogen-filled glovebox. The stir bar is a magnet coated with Teflon. Instantly an mini explosion happened, with black soot and smoke. In the end, I recovered a magnet without the coating of Teflon. Luckily, the above operation was carried in a glovebox, and no injury was reported. However, if the NaK was first submerged in hexanes, no reaction was observed when a stir bar is added. A simplified reaction is shown below
(CF2=CF2)n + NaK = NaF + KF + C
According to Professor James Dye's theory, NaK is best described as Na-K+ because sodium is more electronegative than potassium. When sodium and potassium mix, an electron transfer reaction happened.
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