Blowing stuff up
Writing about web page http://www.theodoregray.com/PeriodicTable/Stories/011.2/
I know almost nothing about chemistry. But I have fond memories of the tiny bit of it I studied at school many years ago. Back then, chemistry teachers routinely made themselves into demi-gods in the eyes of impressionable young boys by doing what can only be described as cool stuff with chemicals. In those days, dropping slivers of sodium into water to watch it combust violently was common-place, as (alas) was playing with mercury.
But any chemistry teacher who was really keen to make an impression knew that the thing to do was take the class outside and drop a larger chunk (maybe 50 grams) of sodium into a pond, with explosive results, and respect bordering on worship from the audience.
I gather they don't do this sort of thing in schools any more. And perhaps that's a good thing: this guy has taken the sodium-plus-water-equals-explosion gag far beyond its logical conclusion, and provided some startling videos of his results. As he says of his 50 gram explosion:-
If we had been anywhere within 15 feet of this explosion, it would have sprayed us with molten sodium and sodium hydroxide. … A lot of people have hurt themselves by going to bigger and bigger pieces thinking it's just going to do more of the same. It doesn't: At some point it turns from a fizzle and flame into a real explosion, like a shotgun.
I relish the memory of my insanely reckless chemistry teachers, but having watched these videos, I think it's probably for the best that schools don't allow this any more, and if you take a look, my guess is that you will too.
(That said, if anyone from chemistry is planning to drop, say, 150 grams of sodium into a lake, give me a call first, would you?)