2648: Chemicals

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It's hard to believe, but lots of kids these days ONLY know how to buy prepackaged molecules.
Title text: It's hard to believe, but lots of kids these days ONLY know how to buy prepackaged molecules.


In this comic, Megan mentions to Cueball that their company spends a lot on chemicals for which you can find formulas online. She suggests assembling chemicals from atoms "bought in bulk," holding a sheet of paper with the empirical formula C6H5NO2, which designates hundreds of compounds including nitrobenzene, niacin, isonicotinic acid, and picolinic acid, followed by their component elements listed with quantities and prices. The ambiguity of chemical formulae is one of the jokes in the comic.

While many expensive chemicals are composed of inexpensive and easily available elements, "assembling" those elements into specific molecules is rarely as simple as Megan implies. That work is the primary purpose of the global chemical industry. In-house chemical synthesis is usually not cost effective, because end users have limited time and are generally unable to leverage the economies of scale inherent in bulk manufacturing by specialist industrial firms.[1] They are also not able to benefit from synergies by simultaneous synthesizing different compounds. However, we don't know whether Megan and Cueball work in a laboratory, factory, or some other industrial setting. If they need chemicals in bulk, or only very small quantities, synthesizing them might be cost effective. In any case, producing chemicals from their constituent elements, or — as is far more common — precursor compounds, is difficult and time-consuming, usually requires expensive equipment, and is often fraught with peril.[2] It's conceivable that this could change as biotechnology, artificial intelligence, and nanotechnology develop, but it is a far fetch given the relative ease of synthesizing chemicals from other chemicals. Nitrobenzene, one of the C6H5NO2 compounds, is an excellent example because it is explosive and extremely toxic, and its synthesis is highly exothermic, making it one of the most dangerous syntheses in the chemical industry.[3] Such issues answer Cueball's question as to why more places don't manufacture their own compounds from atoms. Megan seems to be imagining synthesis as a much simpler process without reactivity, energy release, or hazardous intermediate substances. The characters' naivety also gives rise to the humor of the comic.

"Big Molecule" is an industry nickname like Big Oil or Big Pharma, amusing in its own right, and conceivably implying that the chemical industry is conspiring to prevent end users from synthesizing their own compounds. Big Oil and Big Pharma are real industrial nicknames, referring to large industries run by a relatively small number of massive and hugely profitable companies. These companies are sufficiently wealthy and influential that they exert significant control over the marketplace, and even over government policy. Consequently, many consumers believe that their influence allows them to price products unfairly and prevent competition. "Big Molecule," on the other hand, is not a common term. It could be used to refer to the global chemical industry, but that industry is neither seen as being excessively powerful, nor does it impact consumers as visibly, and so doesn't merit a similar nickname. Literal big molecules tend to be more difficult to synthesize than little ones, with the difficulty increasing more rapidly than the size. Some big molecules such as synthetic DNA are constructed chainwise from sub-units, and in these cases the difficulty is (approximately) linear with size.

Megan is holding a note listing how many of the four types of atoms she needs to build one molecule of the compound she wants to assemble. The paper seems to list prices for buying 6 carbon, 5 hydrogen, 1 nitrogen and 2 oxygen atoms, although the units aren't specified and the very small prices are illegible. At the bottom is a sum showing she needs 14 total, again with an illegible price. She is suggesting buying atoms in bulk, which should be even cheaper than buying them individually. However, this is another layer of humor, as you can neither buy individual atoms or get a price for them, showing her lack of understanding of chemistry. An actual bill of materials for a chemical compound synthesis from constituent elements alone would list the elements converting their number of atoms to moles, then to mass for solids and some fluids or to volume at the available pressure and temperature for other fluids, and then to the purchase price, which would usually need to be rounded up to match the next largest size available from suppliers. Also reagents are usually necessary for syntheses, e.g., reactants, solvents, buffers and catalysts such as enzymes. These can cost more than the compounds' constituents but are sometimes recoverable for reuse, though that may require using additional reagents. In many cases, the cost of the elements would be more than the cost of the compound. For example, purchasing hydrogen and oxygen from which to make water would cost more than water costs.

The title text refers to the fact that older people often complain that "kids these days" don't know how to do things that seemed fundamental to past generations. Randall may have expressed that he dislikes other statements like these in previous comics. It may also refer to the decline of home chemistry sets popular from the late 1700s through the early 1980s that encouraged kids to experiment with basic chemical reactions like generating esters or polymers, or the even older decline in home manufacture of gunpowder as was common in the 1800s. Chemical engineering was more widely practiced during the development of plastics, but far fewer people understand how they are made today. Similarly with automobiles, domesticated crops, and many other technologies that progressed through a period of popular attention but became siloed into industries, corporations, governments, or branches of academia. This is happening now with some software, circuitry, and other technologies, where fewer people know how to build and troubleshoot complex devices and systems. Technology users thus lose their ability to build and repair machines and modify their tools themselves, having to rely on paid services instead. Similar to the makerspace movement, community chemical labs have occasionally been cropping up, where people work together to perform citizen science, including occasional chemical synthesis, by sharing community resources; however, biohacking and structural manufacturing are far more common.

This comic may have been prompted by recent news that scientists have found a way to assemble and change atoms in individual molecules by modifying their bonds.


[Megan and Cueball standing next to each other. Megan has her palms raised.]
Megan: You know how our company spends a lot on expensive chemicals?
Cueball: Yeah?
[Zoom in on Megan who is holding piece of paper up in one hand. The paper has a large chemical formula at the top. Below is a list of the atoms needed, with amount and a price tag in dollars but with unreadable amount. There is a sum total at the bottom beneath a line.]
Megan: Well, I just learned you can look up all of the formulas online!
Megan: We can just buy the atoms in bulk and assemble them here!
Carbon 6 $...
Hydrogen 5 $...
Nitrogen 1 $...
Oxygen 2 $...
Total 14 $...
[Cueball is now on the left of Megan as she is walking past him to the right holding her arms outstretched with her palms up.]
Cueball: I wonder why more places don't do that.
Megan: People have no idea they're getting ripped off by Big Molecule!

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Does anyone know the significance of nitrobenzen, the compound indicated? Per Wikipedia " The production of nitrobenzene is one of the most dangerous processes conducted in the chemical industry because of the exothermicity of the reaction (ΔH = −117 kJ/mol)" but I wonder if there's something else too. 20:07, 20 July 2022 (UTC)

It's almost certainly the exothermic (read: potentially explosive) reaction that he's going for. 20:11, 20 July 2022 (UTC)
It is also the formula of Niacin, one of the B vitamins (same atoms, different arrangement) Possibly this is the point: the molecular formula is ambiguous, there are several well-known chemicals with this formula, with very different properties Zeimusu (talk) 20:58, 20 July 2022 (UTC)

I wouldn't know which way to put this, but "make your own molecules" could be parodying the "build your own PC from bits", "compile your own OS distro", "actually cook food from raw ingredients, not packets" or various other supply/consumer things that some people (those who know enough about what they're doing) will actually do, many people (who don't care to know) won't even consider and some (with a little bit of knowledge, but not actually enough) might find the revelation that they could do some things themselves far more compelling than the valid question of whether they should just leap in and try to do it (making all kinds of mistakes/reinventing various wheels along the way) without further research. 21:14, 20 July 2022 (UTC)

There are also a lot of make-your-own-film-developer nerds, which is a little bit closer in that you're using household items to try to recreate the reactions created by otherwise expensive chemicals. 22:37, 20 July 2022 (UTC)
I never even heard of those. I used to live in a household where there was darkroom equipment, even, so know a little of the process of doing that (more so than academic chemistry lessons) but I'd shy away from trying to substitute like that. If it's a thing, then might be worth linking (when and by who it can be). 10:33, 21 July 2022 (UTC)
Megan could also be so used to using "free and open source" software, where you can download the source code, make some minor modifications for your situation, then compile it and use the executable. Here the source code is easy to get but the compiling process can be much more challenging. Nutster (talk) 16:34, 24 July 2022 (UTC)
Equally could be parodying fallacious thinking in corporate procurement that says 'if we build system x in-house, we won't have have to pay some supplier loads of money to do it', which ignores that the supplier is likely leveraging economies of scale by developing for multiple clients, and ignores the costs of supporting and maintaining the system. 12:14, 21 July 2022 (UTC)

It would appear we have a vandal on the loose again. 22:42, 20 July 2022 (UTC)

How exactly do we block these people? 04:05, 21 July 2022 (UTC)
Maybe the an option is to find out which Reddit forum they're launching from and get it banned from Reddit. They'll do that if the forum is brigading too much
i'm pretty sure the vandals are calling us redditors and they don't use reddit themselves -- 06:58, 21 July 2022 (UTC)
It seems to be typical 4chan terminology. Someone who spent some time being influenced there, or maybe one step removed in their own little chan-wannabe dark cave sitting in some other area of the twilight internet taking most of their prompts from the 'real rebels' who are probably just egging them on for their own meta-amusement, but that the stooge(s) would know it. And the repetitious interleving of vandalism modes employed (which are fairly discernible as different until you find the same source has done two or more of the things at once, unifying their identity) indicate a singular whim, if not a singular actor to perform them, who gradually has added new variations to the repertoir of damage to try to be 'clever'. If anything, it just shows how limited they are. 10:33, 21 July 2022 (UTC)

Request for the wiki: require special permissions to post an image that isn't from xkcd.com, and auto-ban any IP that spams racial slurs. Thecat (talk) 04:48, 21 July 2022 (UTC)


I think the site itself is hijacked, since the edits don't show properly. 06:07, 21 July 2022 (UTC)

undo wasn't working apparently so someone undid the vandalism by blanking the page entirely instead of just manually opening an earlier version and restoring the source from there? i don't get it either -- 06:58, 21 July 2022 (UTC)
It's 2 AM and 110 where I live, and most of my computer usage is accounting software. I'm not very smart at wiki stuff. Sorry 07:05, 21 July 2022 (UTC)

I wonder if we should mention the economic difference between small quantities of chemicals typically used in laboratory experiments compared to bulk quantities for industrial manufacturing. The latter often is cost-effective to do in-house, and the current version of the explanation doesn't make that clear at all. We have no idea if Megan and Cueball work in a lab or a factory! 00:37, 21 July 2022 (UTC) Resolved. 00:44, 21 July 2022 (UTC)

https://www.explainxkcd.com/wiki/index.php/Special:Contributions/ Seems to be the vandal's IP for doing more than just clicking the undo button, as it also vandalized a few talk pages. Almost everything that looks like typing it wasn't fully automated came from that IP172.70.178.103 07:41, 21 July 2022 (UTC)

Not sure it will make any difference but I blocked the IP for three days. --Kynde (talk) 08:08, 21 July 2022 (UTC)

I have semi protected this page for one day. Have not so much knowledge about how it worked. But set up so only auto confirmed users can edit this page. This was requested in the admin portal... --Kynde (talk) 08:07, 21 July 2022 (UTC)

(RESOLVED) Edit request
The link that says, "more than a hundred compounds and ions" should be, "hundreds of compounds" -- that was my fault because I got the original URL wrong; thanks to whomever fixed it. 08:39, 21 July 2022 (UTC)

I wonder if this could be referencing the video game Spacechem? The premise is exactly this, of chemical engineering using individual atoms to form desired chemicals, and it's the type of nerdy game Randall might enjoy - or at least have heard of. -- 09:54, 21 July 2022 (UTC)

SpaceChem was the first thing I thought of reading the comic.

I removed "Similar to the makerspace movement, community chemical labs have been cropping up, where people work together to perform chemical synthesis and other chemistry acts by sharing community resources," because it doesn't seem to be true; see [4]. Maybe someone can think of something similar but less misleading from that paper? 11:52, 22 July 2022 (UTC)

I actually was a very fringe part of a group synthesizing coronavirus tests at a community lab, and have elesewhere participated in groups with community labs. I have some neurological issues and have not yet found a citation or reviewed your reference, but the statement is indeed very true. 12:04, 22 July 2022 (UTC)
There is a reason that we as a society house exploratory chemistry labs inside high schools, colleges and universities, but we allow co-ops and makerspaces to host mechanical and manufacturing tools. It's mostly the greater extent of safety equipment, protocols, supervision, and training compared to hand tools and shop equipment, but also the huge regulatory burden of storing thousands of precursor chemicals, many hundreds of which are likely to be deadly poisons, explosive, radioactive, drugs of abuse, potent carcinogens and teratogens, or just absurdly expensive. Have a look at this video to get an idea of what a modern synthesis lab is like. 15:25, 22 July 2022 (UTC)
From your link: "In this work I describe the design and impacts of a makerspace at the University of Utah, created specifically for chemical engineering curriculum." -- is your concern the phrasing around "cropping up", that the statement implies more labs here than your experience is that there actually are? 12:10, 22 July 2022 (UTC)
If you read about what they actually use the makerspaces for, it's mostly glasswork and manufacturing of lab equipment, not synthesis at all. 14:07, 22 July 2022 (UTC)
These are the guys I spent time near during the coronavirus outbreak. I don't know where their website is now; I've lost the chats. But given that they were doing it in 2015, and your citation against the sentence actually backs it up, I'm planning to bring the sentence back. https://web.archive.org/web/20150920075545/http://www.indielab.co/resources 12:34, 22 July 2022 (UTC)
It looks like they closed their public access to the chem lab in 2018 when they became Librecycle. I'm skeptical that a makerspace-style chem lab is insurable in the US, although with a strict training and certification regime, anything is possible. 14:28, 22 July 2022 (UTC)
that's usually solved by invested effort and finances of the people who care about it, even if it means passing local laws, or taking temporary risks. this page has been so vandalised, please just include everyone's viewpoints and work to improve it. 17:51, 22 July 2022 (UTC)

I agree with the edit summary/history suggesting the discussion of Big Pharma is off-topic, but not terribly so. I follow 1RR here in such borderline cases. 14:39, 22 July 2022 (UTC) The revision is excellent. 18:00, 22 July 2022 (UTC)

You could take the "savings" one step further: Instead of buying dozens of different atoms, just buy a bunch of protons, neutrons, and electrons! Only 3 particle types needed! You may need to work out some minor issues with packaging and transport, however. 21:13, 22 July 2022 (UTC)

The difference being that you can buy a mole of carbon but not any useful quantity of those particles :-) 21:34, 22 July 2022 (UTC)