Skip to main content

Sunday chemistry blogging: catalysts

Ok, it's a day late, sorry, and it will be a bit short.  But during the camp when we were having a bit of trouble getting a fire started (meaning a guy kept throwing huge pieces of wood on before it got started), someone produced a plastic bag.  "Any of you taken chemistry?  This is called a catalyst!" he said, and cast the bag into the flames, where it burned about like you'd expect (very quickly).  I imagine this reflects the popular understanding of catalyst as something that makes a reaction go faster, like pouring gasoline on a fire.

Of course, I couldn't help gleefully pointing out that I actually have a degree in chemistry, and that the guy's definition of catalyst was completely wrong.  (Why study science if you can't be an asshole about it at least once in awhile?)  Here's the real definition: a catalyst is something that changes the rate of a reaction while not being consumed by the reaction.  So the common movie trope when someone sprinkles a bit of "catalyst" into a big vat of chemicals and it starts to boil ferociously is close to the mark, but it's worth thinking about why this is.

The critical part of the catalyst definition above is the "not consumed" part.  Most catalysts do something like this:

R1 + R2 + C → R1-C-R2 → P + C

Here we've got a reaction where two reactants, R1 and R2, are reacting to form a single product P.  The catalyst, C, is helping things out by forming an intermediate stage on the way to the product—it's kind of like a chemical matchmaker that steps back after making introductions.  (Like anything in science, the details of each individual catalytic reaction can get stupendously complex, and sometimes work in ways completely different from my picture above.  But this is a decent way of thinking about it in general.)

Most catalysts are used to speed up reactions (called positive catalysis), but some are used to slow them down (negative catalysis).  Now you too can correct people at parties!

Comments

Popular posts from this blog

Why Did Reality Winner Leak to the Intercept?

So Reality Winner, former NSA contractor, is in federal prison for leaking classified information — for five years and three months, the longest sentence of any whistleblower in history. She gave documents on how Russia had attempted to hack vendors of election machinery and software to The Intercept , which completely bungled basic security procedures (according to a recent New York Times piece from Ben Smith, the main fault lay with Matthew Cole and Richard Esposito ), leading to her capture within hours. Winner recently contracted COVID-19 in prison, and is reportedly suffering some lingering aftereffects. Glenn Greenwald has been furiously denying that he had anything at all to do with the Winner clusterfuck, and I recently got in an argument with him about it on Twitter. I read a New York story about Winner, which clearly implies that she was listening to the Intercepted podcast of March 22, 2017 , where Greenwald and Jeremy Scahill expressed skepticism about Russia actual...

The Setswana Grammar Manual

One of my few successes during my service here was formatting the Peace Corps South Africa grammar manual for Setswana, written mostly by Art Chambers, an SA16 volunteer.  For anyone wanting to learn Setswana, I reckon it's a pretty good primer, so I present it for free here .  If you think it sucks and you want to make changes, or you'd like to take a look at the raw TeX file, you can find it here .

On Refusing to Vote for Bloomberg

Billionaire Mike Bloomberg is attempting to buy the Democratic nomination. With something like $400 million in personal spending so far, that much is clear — and it appears to be working at least somewhat well, as he is nearing second place in national polls. I would guess that he will quickly into diminishing returns, but on the other hand spending on this level is totally unprecedented. At this burn rate he could easily spend more than the entire 2016 presidential election cost both parties before the primary is over. I published a piece today outlining why I would not vote for Bloomberg against Trump (I would vote for Sanders, Warren, Buttigieg, Klobuchar, or Biden), even though I live in a swing state. This got a lot of "vote blue no matter who" people riled up . They scolded me and demanded that I pre-commit to voting for Bloomberg should he win the nomination. The argument as I understand it is to try to make it as likely as possible that whatever Democrat wins t...