"Hydrofluoric acid is probably the most feared chemical compound that there is," says Sir Martyn Poliakoff, a chemistry professor at the University if Nottingham. "The reason it's so feared is that it is very corrosive. It will burn through human skin, even quite a small exposure on your skin can cause a heart attack."

Hydrofluoric acid will also burn through glass. Naturally, the first thing you should do once you obtain some is immerse a lit incandescent bulb into a beaker of it.

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