Author Topic: Phyllis and the chemistry of the universe  (Read 1000 times)

Crowley

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Phyllis and the chemistry of the universe
« on: October 04, 2017, 07:48:58 pm »
Since I see people bring up things here that seem factually incorrect, I thought I'd mention this here: Phyllis at the Oculus says that the chemical composition of human beings is mainly carbon, hydrogen, nitrogen and oxygen. This is correct. However, she is incorrect when she claims these are "four out of five most common elements". On a galactic scale, nitrogen is only in seventh place when it comes to most abundant chemicals. Above it are iron and neon.

PhrygianDominant

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Re: Phyllis and the chemistry of the universe
« Reply #1 on: October 05, 2017, 05:34:01 pm »
You are correct. I think I got that particular datum from one of Neil deGrasse Tyson's lectures, and doing a quick Google search I found this quote from him: "The four most common chemically active elements in the universe - hydrogen, oxygen, carbon and nitrogen - are the four most common elements of life on Earth. We are not simply in the universe. The universe is in us." Here he says "chemically active" elements, which is an important distinction, but then again he himself might've accidentally omitted it during that lecture and I didn't verify it before I wrote that piece of dialogue.

However, there's a certain thing I'd like to point out. Nitrogen comes seventh in the universe if we look at the mass fraction, but things can be a bit different if we look at the mole fraction.

If I'm reading this thing correctly, here nitrogen seems more abundant than neon and iron -> https://www.webelements.com/periodicity/abundance_universe_a/

Also, interestingly -> https://en.wikipedia.org/wiki/Abundance_of_the_chemical_elements - if you scroll to Solar System and sort the list by atom fraction in parts per million, Nitrogen-14 is fifth again (but that's just the Solar System).
Similar thing here, but now it's sixth -> http://www.knowledgedoor.com/2/elements_handbook/element_abundances_in_the_solar_system.html (again only for the Solar System).

In any case, thanks for the correction. I'll modify the dialogue for the next version. Even though Underrailers live underground and haven't even seen the sky or the stars in their life, she's been studying in the Oculus(!) for a while and should have good estimates; some characters are allowed to be wrong, as they often are in real life, but not in this case. Cheers! :)

Crowley

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Re: Phyllis and the chemistry of the universe
« Reply #2 on: October 06, 2017, 06:52:24 pm »
I can see how that could differ in places depending on interpretations and the latest data. The sources I looked up disagreed on which way around neon and iron are. Anyway, happy to be of assistance!

Styg

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Re: Phyllis and the chemistry of the universe
« Reply #3 on: October 07, 2017, 07:37:07 am »
They've already learned from the Mainframe that there are no such thing as atoms and it was just a silly 20th century theory. I don't know why Phyllis is pulling your leg, though, we'll fix that.