@tsarstepan,
Not sure if this us an urban legend or not, but apparently some sort of middle schooler I believe made a science project for a science fair I believe they are called? Anyway, the sort of thing that parents visit to look at all of the students creations.
Anyways, said student had made a petition to ban dihydrogen monoxide from America, and he made a list with some of those same 'properties' listed, such as it being a major component of acid rain and the like.
According to the tale, many people actually signed the petition.
As for the level of schooling of the average american, while I'm usually rather taken aback by it, this time, I sorta feel the need to defend it: the specific bit you are referring to is to translate the spoken name of a chemical substance to a chemical formula, and then being able to convert that in your head to the appropriate substance.
If you've been out of highschool for a bunch of years, and you never had much interest in that sort of thing anyway(and how many people really do?), then I can understand forgetting it. It's not actually a necessity to know that H2O means water in today's society: most people call water water, after all.
