Ever wondered what would happen if you poured bleach into coke? (DON’T TRY THIS AT HOME!!!!!!)
Bleach contains highly reactive molecules, like the loosely-bound sodium hypochlorite that functions as the active ingredient in standard chlorine bleaches like Clorox. When it’s poured onto a stain, (or into a glass of coke) the chlorine-oxygen group sticks to the pigment molecules, bending them out of shape and changing which wavelengths excite their electrons. Like a bent radio antenna, those molecules can no longer absorb or reflect the electromagnetic energy they were previously sensitive to, and the photons pass on through them. When we bleach a ketchup stain, it may look like it comes out of the fabric, but the reality is that the lycopene molecules are still there—they’ve just been rendered invisible by all the extra atoms that have been stuck onto them!