[Shenglong]

You're probably correct that those 19/20 won't know at first what dihydrogen monoxide is. The pressing question is though, whether those 19 would/should call the water commission before either:

A. Thinking about it

B. Spelling the chemical formula out

C. Googling it

This has very little to do with being high-and-mighty. I don't believe the author's point was to illustrate how uneducated the general population is, but rather, highlight how little thinking/work the general population does before complaining/protesting/getting up in arms.

[drdaeman]

I wonder how this discussion would go if they'd call it oxidane.