It Makes Chlorine Gas
This one may or may not be based on a real life event. And by ‘may or may not be based on’ I mean ‘totally did happen’. And by ‘a real life event’ I mean ‘last Wednesday’. This is why chemistry is important. Stay in school, kids.
Truth be told, this amount will likely not cause the hyperbolic reaction displayed in the comic. Excessive amounts CAN oxidize Chlorine gas which is toxic, so don’t play around with the stuff.