3047: Rotary Tool

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Chemical Formula

|< < Prev #3200 (January 28, 2026)

Title text: Some of the atoms in the molecule are very weakly bound.

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Explanation

This is one of 60 incomplete explanations: This page was created by all of the carbon in the universe. Don't remove this notice too soon. If you can fix this issue, edit the page!

This supposed "chemical formula for the universe" merely lists the numbers of atoms of each element that are thought to exist in the observable universe. Usually, chemical formulae imply rather more of a discrete binding together of the atoms involved. They also represent a single molecule of the substance, rather than trying to cover the entire number of atoms in the whole quantity under consideration.

This may be poking some fun at the relative usefulness (or rather, uselessness) of chemical formulas for large organic molecules. While it is a useful concept for teaching people about chemistry and balancing equations, and it was useful in the early days of chemistry to try to categorize and learn about molecules via stoichiometry - it does not give much useful information, such as its structure. For example, even the simple formula C₁₁H₁₅NO₂ has 302 registered isomers.^{[actual citation needed]} Many of them are NOT good to eat.^{[citation needed]} For other purposes, formulae may group the components accordingly, such as CH₃CCl₃ (simplifies to C₂H₃Cl₃, as does an isomer) or [NH₄]₂CO₃ (not usually identified as CH₈O₃N₂, and not strictly an organic compound either).

As is common practice for real compounds that contain organic structures or substructures, the numbers of atoms of carbon and hydrogen are listed before all of the others; the others are listed in alphabetical order. There are estimated to be 10⁸⁰ atoms of hydrogen (H), by far the most common element in the universe. The next most common element, helium (He), is a long way to the right in the list, and out of view, but would be about a third as many as the hydrogens.

In reality, there is not a fixed number of atoms of each element across the lifetime of the universe. The matter originally created in the Big Bang was unbound protons and neutrons. In the first few minutes, some of these combined to form lightweight nuclei, but most remained as protons (i.e. the nuclei of hydrogen atoms). Other more complex atoms, up to atomic mass 56, formed later (and are still being formed) as a result of stellar nucleosynthesis. Still more massive nuclei have been and are being formed via supernova nucleosynthesis. Although the proportions of these atoms depend in a complex way on the fusion processes involved, and on the stabilities of those nuclei, the most massive atoms are generally both short-lived and less favored to form, so their elemental abundances in the universe are very small. As shown above, the number of americium (Am) atoms is much smaller than those of any other element in the visible part of the "formula". There are slightly fewer atoms of americium in the entire universe than the total number of atoms of hydrogen and oxygen in 1.0 L of liquid water.

The title text is probably referencing gravity, because, for the most part, these atoms would be "held together" only by gravity, and it is a very weak bond indeed.

The numbers of atoms are large, but they are not nameless. Using the long and short scales, these numbers can be described as:

Pos	Symb	Name	Quantity	Short Scale name	Long Scale name(s)	Ranked quantity*
1	C	Carbon	1076	Ten quattuorvigintillion	Ten thousand duodecillion Ten duodecilliard	4
2	H	Hydrogen	1080	One hundred quinvigintillion	One hundred tridecilllion	1
3	Ac	Actinium	1067	Ten unvigintillion	Ten undecillion	≈84
4	Ag	Silver	1069	One duovigintillion	One thousand undecillion One undecilliard	≈68
5	Al	Aluminium Aluminum	1075	One quattuorvigintillion	One thousand duodecillion One duodecilliard	14
6	Am	Americium	1026	One hundred septillion	One hundred quadrillion	≈84
7	Ar	Argon	1075	One quattuorvigintillion	One thousand duodecillion One duodecilliard	11
8	As	Arsenic	1070	Ten duovigintillion	Ten thousand undecillion Ten undecilliard	≈40
9	At	Astatine	1047	One hundred quattuordecillion	One hundred thousand septillion One hundred septilliard	≈84
10	Au	Gold	1069	One duovigintillion	One thousand undecillion One undecilliard	≈68
11	B	Boron	1071	One hundred duovigintillion	One hundred thousand undecillion One hundred undecilliard	≈61
12	Ba	Barium	1070	Ten duovigintillion	Ten thousand undecillion Ten undecilliard	≈33
13	Be	Beryllium	1071*	One hundred duovigintillion	One hundred thousand undecillion One hundred undecilliard	≈61
43*	He	Helium	1079*	Ten quinvigintillion	Ten tridecilllion	2
73*	O	Oxygen	1078*	One quinvigintillion	One tridecilllion	3

* - Information not provided by the comic; Source for ranked data, in particular, does not 'entirely' agree with the quantities that are given in the comic.

The formula as it appears in the comic is truncated. The complete formula of the universe in this style (but arranged in decreasing order of abundance after carbon, which also happens to place hydrogen immediately after) would be C₁₀⁷⁷ H₁₀⁸⁰ He₁₀⁷⁹ O₁₀⁷⁸ Ne₁₀⁷⁶ N₁₀⁷⁶ Fe₁₀⁷⁶ S₁₀⁷⁶ Mg₁₀⁷⁵ Si₁₀⁷⁵ Ar₁₀⁷⁵ Ni₁₀⁷⁵ Ca₁₀⁷⁵ Al₁₀⁷⁵ Na₁₀⁷⁵ Cr₁₀⁷⁵ Ti₁₀⁷⁴ Mn₁₀⁷⁴ P₁₀⁷⁴ K₁₀⁷⁴ V₁₀⁷⁴ Cl₁₀⁷⁴ Co₁₀⁷⁴ F₁₀⁷³ Zn₁₀⁷³ Ge₁₀⁷³ As₁₀⁷² Br₁₀⁷² Li₁₀⁷² Sc₁₀⁷² Cu₁₀⁷² Ga₁₀⁷² Se₁₀⁷² Kr₁₀⁷² Rb₁₀⁷² Sr₁₀⁷² Zr₁₀⁷² Te₁₀⁷² Xe₁₀⁷² Ba₁₀⁷² Ce₁₀⁷² Pb₁₀⁷² B₁₀⁷¹ Be₁₀⁷¹ Y₁₀⁷¹ Nb₁₀⁷¹ Mo₁₀⁷¹ Ru₁₀⁷¹ Pd₁₀⁷¹ Cd₁₀⁷¹ Sn₁₀⁷¹ I₁₀⁷¹ La₁₀⁷¹ Pr₁₀⁷¹ Nd₁₀⁷² Sm₁₀⁷¹ Gd₁₀⁷¹ Dy₁₀⁷¹ Er₁₀⁷¹ Yb₁₀⁷¹ Os₁₀⁷¹ Ir₁₀⁷¹ Pt₁₀⁷¹ Hg₁₀⁷¹ Rh₁₀⁷⁰ Ag₁₀⁷⁰ In₁₀⁷⁰ Sb₁₀⁷⁰ Cs₁₀⁷⁰ Eu₁₀⁷⁰ Tb₁₀⁷⁰ Ho₁₀⁷⁰ Tm₁₀⁷⁰ Lu₁₀⁷⁰ Hf₁₀⁷⁰ Ta₁₀⁷⁰ W₁₀⁷⁰ Re₁₀⁷⁰ Au₁₀⁷⁰ Tl₁₀⁷⁰ Bi₁₀⁷⁰ Th₁₀⁷⁰ U₁₀⁷⁰ Tc₁₀⁰ Pm₁₀⁰ Po₁₀⁰ At₁₀⁰ Rn₁₀⁰ Fr₁₀⁰ Ra₁₀⁰ Ac₁₀⁰ Pa₁₀⁰ Np₁₀⁰ Pu₁₀⁰ Am₁₀⁰ Cm₁₀⁰ Bk₁₀⁰ Cf₁₀⁰ Es₁₀⁰ Fm₁₀⁰ Md₁₀⁰ No₁₀⁰ Lr₁₀⁰ Rf₁₀⁰ Db₁₀⁰ Sg₁₀⁰ Bh₁₀⁰ Hs₁₀⁰ Mt₁₀⁰ Ds₁₀⁰ Rg₁₀⁰ Cn₁₀⁰ Nh₁₀⁰ Fl₁₀⁰ Mc₁₀⁰ Lv₁₀⁰ Ts₁₀⁰ Og₁₀⁰ according to some broad stroke estimates of abundance.

Transcript

This is one of 40 incomplete transcripts: Don't remove this notice too soon. If you can fix this issue, edit the page!

[A long panel with a chemical formula trailing off the right side]

C_10⁷⁶ H_10⁸⁰ Ac_10⁶⁷ Ag_10⁶⁹ Al_10⁷⁵ Am_10²⁶ Ar_10⁷⁵ As_10⁷⁰ At_10⁴⁷ Au_10⁶⁹ B_10⁷¹ Ba_10⁷⁰ Be

[Caption below the panel:] The approximate chemical formula for the universe

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Discussion

How come it's at 0.017 RPM for a minute?? and yet 1 RPM for a second? pls fix this randall Midnightvortigaunt (talk) 18:01, 5 February 2025 (UTC)

Its 0.017 RPM for the minute hand. The minute hand revolves once per hour or at 1/60 RPM ≈ 0,017 RPM --172.71.148.59 18:14, 5 February 2025 (UTC)

Ohhh that makes sense I didn't think about it like that Midnightvortigaunt (talk) 19:27, 5 February 2025 (UTC)

Mr.Dude (talk) 17:20, 7 February 2025 (UTC) I wonder what torque is needed to launch the average backyard telescope worthy of a tracking mount at Mach 8 given standard state pressures and temperatures of perhaps average conditions found in Randall’s back yard.

How come the comment above is invisible to me? 172.68.245.229 18:03, 5 February 2025 (UTC)

Possibly because people indented with spaces rather than with colons? 162.158.79.77 19:40, 5 February 2025 (UTC)

72 RPM for a record player...? 162.158.74.25 18:08, 5 February 2025 (UTC)

I could only find 78 RPM disks in the german wikipedia. 172.70.114.56 18:41, 5 February 2025 (UTC)

I came here to make the same comment: 72 is most probably a typo. The old records (at this date, very old, since the transition to vinyl records was 1948 to 1958 (in the US)) were 78 rpm, not 72 rpm https://en.wikipedia.org/wiki/Phonograph_record Rps (talk) 19:30, 5 February 2025 (UTC)

72 is (for example) relevent to font sizes (size 1 = 1/72 of an inch, size 72 = 1 inch), which might therefore have envaigled Randall's head for numbers by a different route, and got him confused. Conceivably he has had to deal with playing old 78s, but probably not for a long time... even the retro-revival of vinyl, recently, has probably not had quite so many old old records released to fill such nostalgic needs. So an easy brain-fudge/thinko to trip over on. 162.158.74.48 00:54, 6 February 2025 (UTC)

There used to be a record label call 72RPM records. 172.69.229.146 (talk) 19:07, 5 February 2025 (UTC) (please sign your comments with ~~~~)

We need one of those tables in here. DollarStoreBa'al (talk) 18:37, 5 February 2025 (UTC)

I made a change to the explanation that all of these numbers are realistic because, I checked out the speed of dental drills and they really do rotate that fast. I haven't checked out all of the other tools, but I suspect that they are also accurate. If you find that any of them are misstated, please correct my correction. Rtanenbaum (talk) 22:38, 5 February 2025 (UTC)

TABLE REQUEST When someone uploads a table, I'd like to recommend a second column for the frequency / reciprocal of the speed. "0.000000000073 minutes" is one every 13.7 billion minutes, or ~26,000 years. Thanks! 172.70.46.107 20:20, 5 February 2025 (UTC)

Me again. Should the column header "revolution time" be "rotation time"? In every instance, the axis of motion is within the object itself; even the second/minute/hour hands go around the axis. 141.101.76.73 16:41, 6 February 2025 (UTC)

TRIVIA 16 2/3 RPM phonographs were used for some voice-recorings back in the day. 172.68.26.24 21:01, 5 February 2025 (UTC)

My parent's old record player (60's, probably) had 4 possible speeds: 16, 33, 45, 78. By the early 80's the current ones only had 33 and 45. Rps (talk) 16:59, 7 February 2025 (UTC)

Album goes back to stacks of 78s. A symphony or opera would be 2, 3, 4 or more disks. They were bound like a photo-album with a leaf for each disk. "78" wasn't "standardized" until the format was fading. 3600-rpm motor and 46-tooth gear is incomplete (one tooth gear??) Early discs were from 60 to 130 rpm. Users would adjust speed by ear (also to ease pitch-matching for karaoke). Only as LPs arrived did someone invent the number "78.26 rpm" (no recordplayer and few lathes of the period were near that accurate). --PRR (talk) 02:34, 6 February 2025 (UTC)

Indeed, my parents had a large collection of old records and at least one had a speed marking of 80rpm.--172.68.186.43 09:17, 6 February 2025 (UTC)

With wind-up players, a lot of them started off playing at one speed and ended playing at a completely different one anyway...172.68.186.50 09:43, 6 February 2025 (UTC)

I suspect there's not many consumers needing a Uranium Enrichment Centrifuge... at least outside of a few countries in the Middle East. --172.70.58.6 08:50, 6 February 2025 (UTC)

Might face some regulatory / export license issues too.172.70.86.129 11:34, 6 February 2025 (UTC)

I feel like there was a lost opportunity to have Dr. Who's Sonic Screwdriver on the list. Maybe the rpms are unknown.162.158.159.107 13:05, 6 February 2025 (UTC)

The table says that 0.00070 "seems off; a sidereal day is 23.93 hours". That's just because (like all of the other settings) 0.00070 is quoted with only 2 significant digits. Every period between 23.64 and 23.98 hours would round to 0.00070 RPM. 162.158.134.199 13:58, 6 February 2025 (UTC)

The question I have is: why are dental drill speeds so high? 172.70.247.92 17:21, 6 February 2025 (UTC)

"why are dental drill speeds so high?" It hurts less. (Are you old enough to remember routine use of belt-driven dental drills?) You can cut a given amount of material (wood, steel, tooth) quickly with heavy force or high speed. Neither is really fun, but hi-speed is generally preferred. --PRR (talk) 19:08, 6 February 2025 (UTC)

Although some materials behave badly to heat (either work-hardening, for some alloys, or melting/burning, like plastics) and that's why variable-speed hand-drills/etc usefully have low speeds (for essentially the same force, when that's done via reostat rather than an actual gearbox). On the few occasions I've had my teeth drilled, I'm pretty sure I've detected the pungent smell of fried tooth-fragments, but it was nothing like as strong as smelling my own nose-flesh being burnt one of the times I had it cauterised to try (and fail) to prevent excessive nosebleeds. 172.69.79.139 21:15, 6 February 2025 (UTC)

The latest NMR CPMAS probes send their rotors to go at 9.6 Mrpm, M=mega. [1] --172.69.109.172 21:56, 7 February 2025 (UTC)

Should we list the rotor diameters to achieve the mach 8 speed mentioned in the title text in the table? I don't think that we should. guess who (if you desire conversing | what i have done) 06:01, 24 February 2025 (UTC)

I (obviously since I worked it all out) think it is in the spirit of the ridiculous idea of the comic and XKCD generally to do these calculations. That said, I'm getting different numbers than your update to make it Mach 8. Denver87 (talk) 16:21, 24 February 2025 (UTC)

I get the following: 4,799au, 74,866km, 37,733km, 3,144km, 52.4km, 1,588m, 1,165m, 728m, 175m, 34.9m, 21.0m, 149.7cm, 87.3cm, 174.7mm. Denver87 (talk) 16:21, 24 February 2025 (UTC)

Happy to share calculation notes, but here's the example for the dental drill: 300,000rpm = 5,000 rps; diameter of: 174.7mm --> circumference of: pi * 174.7mm = 548.8mm; 548.8mm * 5000rps = 2,744,000mm/sec = 2744m/sec; Mach 8 = 8 * 343m/sec = 2744m/sec. Denver87 (talk) 16:21, 24 February 2025 (UTC)

If you agree with the calculations, one of us can at least update it. Denver87 (talk) 16:21, 24 February 2025 (UTC)
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