A kid followed directions found online to make an alcohol and chlorine bomb in a 2-liter bottle, as featured in many YouTube videos. The result? Scars on hands and face, eyelashes burned off, and temporarily blinded for the next 6 months (give or take).
The lesson? Don't try this at home if you don't know what you're doing. IF you have access to a full face shield, goggles (don't wear contact lenses), body armor, thick protective gloves, and so on, you might be able to get away with it, but I wouldn't suggest trying. As for me... there's a reason I went into a math-heavy observational science field: I don't like things that can kill me.