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		<id>https://www.explainxkcd.com/wiki/index.php?title=3200:_Chemical_Formula&amp;diff=404516</id>
		<title>3200: Chemical Formula</title>
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				<updated>2026-01-29T03:22:45Z</updated>
		
		<summary type="html">&lt;p&gt;2600:6C56:7800:11BB:B5D1:A120:F5A7:F8AF: /* Explanation */ actaul citation needed - note that html comments suggest that this information is incomplete - please fix it if you can&lt;/p&gt;
&lt;hr /&gt;
&lt;div&gt;{{comic&lt;br /&gt;
| number    = 3200&lt;br /&gt;
| date      = January 28, 2026&lt;br /&gt;
| title     = Chemical Formula&lt;br /&gt;
| image     = chemical_formula_2x.png&lt;br /&gt;
| imagesize = 740x225px&lt;br /&gt;
| noexpand  = true&lt;br /&gt;
| titletext = Some of the atoms in the molecule are very weakly bound.&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
==Explanation==&lt;br /&gt;
{{incomplete|This page was created by the carbon in the universe . Don't remove this notice too soon.}}&lt;br /&gt;
The supposed &amp;quot;chemical formula for the universe&amp;quot; merely lists the numbers of atoms of each element. 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 10&amp;lt;sup&amp;gt;80&amp;lt;/sup&amp;gt; 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.&lt;br /&gt;
&lt;br /&gt;
These numbers are large, but they are not nameless. Using the {{w|long and short scales}}, these numbers can be described as:&lt;br /&gt;
{| class=&amp;quot;wikitable sortable&amp;quot;&lt;br /&gt;
!Pos!!Symb!!Name                  !!Quantity                               !!Short Scale name             !!Long Scale name(s)                                           !!Ranked quantity*&lt;br /&gt;
|-&lt;br /&gt;
|  1|| C  ||Carbon                ||data-sort-value=&amp;quot;1e76&amp;quot;|10&amp;lt;sup&amp;gt;76&amp;lt;/sup&amp;gt; ||Ten quattuorvigintillion     ||Ten thousand duodecillion&amp;lt;br/&amp;gt;Ten duodecilliard              ||4&lt;br /&gt;
|-&lt;br /&gt;
|  2|| H  ||Hydrogen              ||data-sort-value=&amp;quot;1e80&amp;quot;|10&amp;lt;sup&amp;gt;80&amp;lt;/sup&amp;gt; ||One hundred quinvigintillion ||One hundred tridecilllion                                    ||1&lt;br /&gt;
|-&lt;br /&gt;
|  3|| Ac ||Actinium              ||data-sort-value=&amp;quot;1e67&amp;quot;|10&amp;lt;sup&amp;gt;67&amp;lt;/sup&amp;gt; ||Ten unvigintillion           ||Ten undecillion                                              ||data-sort-value=&amp;quot;84&amp;quot;|≈84&lt;br /&gt;
|-&lt;br /&gt;
|  4|| Ag ||Silver                ||data-sort-value=&amp;quot;1e69&amp;quot;|10&amp;lt;sup&amp;gt;69&amp;lt;/sup&amp;gt; ||One duovigintillion          ||One thousand undecillion&amp;lt;br/&amp;gt;One undecilliard                ||data-sort-value=&amp;quot;68&amp;quot;|≈68&lt;br /&gt;
|-&lt;br /&gt;
|  5|| Al ||Aluminium&amp;lt;br/&amp;gt;Aluminum||data-sort-value=&amp;quot;1e75&amp;quot;|10&amp;lt;sup&amp;gt;75&amp;lt;/sup&amp;gt; ||One quattuorvigintillion     ||One thousand duodecillion&amp;lt;br/&amp;gt;One duodecilliard              ||14&lt;br /&gt;
|-&lt;br /&gt;
|  6|| Am ||Americium             ||data-sort-value=&amp;quot;1e26&amp;quot;|10&amp;lt;sup&amp;gt;26&amp;lt;/sup&amp;gt; ||One hundred septillion       ||One hundred quadrillion                                      ||data-sort-value=&amp;quot;84&amp;quot;|≈84&lt;br /&gt;
|-&lt;br /&gt;
|  7|| Ar ||Argon                 ||data-sort-value=&amp;quot;1e75&amp;quot;|10&amp;lt;sup&amp;gt;75&amp;lt;/sup&amp;gt; ||One quattuorvigintillion     ||One thousand duodecillion&amp;lt;br/&amp;gt;One duodecilliard              ||11&lt;br /&gt;
|-&lt;br /&gt;
|  8|| As ||Arsenic               ||data-sort-value=&amp;quot;1e70&amp;quot;|10&amp;lt;sup&amp;gt;70&amp;lt;/sup&amp;gt; ||Ten duovigintillion          ||Ten thousand undecillion&amp;lt;br&amp;gt;Ten undecilliard                 ||data-sort-value=&amp;quot;40&amp;quot;|≈40&lt;br /&gt;
|-&lt;br /&gt;
|  9|| At ||Astatine              ||data-sort-value=&amp;quot;1e47&amp;quot;|10&amp;lt;sup&amp;gt;47&amp;lt;/sup&amp;gt; ||One hundred quattuordecillion||One hundred thousand septillion&amp;lt;br/&amp;gt;One hundred septilliard  ||data-sort-value=&amp;quot;84&amp;quot;|≈84&lt;br /&gt;
|-&lt;br /&gt;
| 10|| Au ||Gold                  ||data-sort-value=&amp;quot;1e69&amp;quot;|10&amp;lt;sup&amp;gt;69&amp;lt;/sup&amp;gt; ||One duovigintillion          ||One thousand undecillion&amp;lt;br/&amp;gt;One undecilliard                ||data-sort-value=&amp;quot;68&amp;quot;|≈68&lt;br /&gt;
|-&lt;br /&gt;
| 11|| B  ||Boron                 ||data-sort-value=&amp;quot;1e71&amp;quot;|10&amp;lt;sup&amp;gt;71&amp;lt;/sup&amp;gt; ||One hundred duovigintillion  ||One hundred thousand undecillion&amp;lt;br/&amp;gt;One hundred undecilliard||data-sort-value=&amp;quot;61&amp;quot;|≈61&lt;br /&gt;
|-&lt;br /&gt;
| 12|| Ba ||Barium                ||data-sort-value=&amp;quot;1e70&amp;quot;|10&amp;lt;sup&amp;gt;70&amp;lt;/sup&amp;gt; ||Ten duovigintillion          ||Ten thousand undecillion&amp;lt;br&amp;gt;Ten undecilliard                 ||data-sort-value=&amp;quot;33&amp;quot;|≈33&lt;br /&gt;
|-&lt;br /&gt;
| 13|| Be ||Beryllium             ||data-sort-value=&amp;quot;1e71&amp;quot;|10&amp;lt;sup&amp;gt;71&amp;lt;/sup&amp;gt;*||One hundred duovigintillion  ||One hundred thousand undecillion&amp;lt;br/&amp;gt;One hundred undecilliard||data-sort-value=&amp;quot;61&amp;quot;|≈61&lt;br /&gt;
|-&lt;br /&gt;
|data-sort-value=&amp;quot;43&amp;quot;|43*||He||Helium||data-sort-value=&amp;quot;3e79&amp;quot;|10&amp;lt;sup&amp;gt;79&amp;lt;/sup&amp;gt;*||Ten quinvigintillion      ||Ten tridecilllion                                            ||2&lt;br /&gt;
|-&lt;br /&gt;
|data-sort-value=&amp;quot;73&amp;quot;|73*||O ||Oxygen||data-sort-value=&amp;quot;1e78&amp;quot;|10&amp;lt;sup&amp;gt;78&amp;lt;/sup&amp;gt;*||One quinvigintillion      ||One tridecilllion                                            ||3&lt;br /&gt;
|}&lt;br /&gt;
:&amp;lt;nowiki&amp;gt;*&amp;lt;/nowiki&amp;gt; - 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.&lt;br /&gt;
&lt;br /&gt;
The matter originally created in the Big Bang was unbound protons and neutrons. In the first few minutes, {{w|Big Bang nucleosynthesis|some of these combined to form lightweight nuclei}}, but most remained as protons, i.e. the nuclei of hydrogen atoms. Other, more complex atoms formed later as a result of {{w|stellar nucleosynthesis}}, up to atomic mass 56. Still more massive nuclei have been formed via {{w|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 less favored to form and short-lived, 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 &amp;quot;formula&amp;quot;. There are slightly fewer atoms of americium in the entire universe than the total number of atoms of hydrogen and oxygen in 1.0&amp;amp;#8239;L of liquid water.&lt;br /&gt;
&lt;br /&gt;
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. For example even the simple formula C&amp;lt;sub&amp;gt;11&amp;lt;/sub&amp;gt;H&amp;lt;sub&amp;gt;15&amp;lt;/sub&amp;gt;NO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; has 302 registered isomers.{{actual citation needed}} Many of them are NOT good to eat.{{cn}}&lt;br /&gt;
&lt;br /&gt;
The formula as it appears in the comic is truncated. The complete formula of the universe in this style (but arranged in order of abundance after carbon) would be  C₁₀⁷⁷H₁₀⁸⁰ He₁₀⁷⁹ O₁₀⁷⁸ Ne₁₀⁷⁶ N₁₀⁷⁶ Mg₁₀⁷⁵ Si₁₀⁷⁵&amp;lt;!--Ar here?--&amp;gt;  Fe₁₀⁷⁴ S₁₀⁷³Ni₁₀⁷² Ca₁₀⁷² Al₁₀⁷¹&amp;lt;!--B here?--&amp;gt;&amp;lt;!--Be here?--&amp;gt;  Na₁₀⁷⁰&amp;lt;!--As here?--&amp;gt;&amp;lt;!--Br here?--&amp;gt;&amp;lt;!--Li here?--&amp;gt; Cr₁₀⁶⁹ Ti₁₀⁶⁸ Mn₁₀⁶⁸ P₁₀⁶⁷ K₁₀⁶⁶ V₁₀⁶⁵ Cl₁₀⁶⁴ F₁₀⁶³ Sc₁₀⁶² Co₁₀⁶² Cu₁₀⁶¹ Zn₁₀⁶⁰ Ga₁₀⁵⁹ Ge₁₀⁵⁸ Se₁₀⁵⁷ Kr₁₀⁵⁶ Rb₁₀⁵⁵ Sr₁₀⁵⁴ Y₁₀⁵³ Zr₁₀⁵² Nb₁₀⁵¹ Mo₁₀⁵⁰ Tc₁₀⁴⁹ Ru₁₀⁴⁸ Rh₁₀⁴⁷ Pd₁₀⁴⁶ Ag₁₀⁴⁵ Cd₁₀⁴⁴ In₁₀⁴³ Sn₁₀⁴² Sb₁₀⁴¹ Te₁₀⁴⁰ I₁₀³⁹ Xe₁₀³⁸ Cs₁₀³⁷ Ba₁₀³⁶ La₁₀³⁵ Ce₁₀³⁴ Pr₁₀³³ Nd₁₀³² Sm₁₀³¹ Eu₁₀³⁰ Gd₁₀²⁹ Tb₁₀²⁸ Dy₁₀²⁷ Ho₁₀²⁶ Er₁₀²⁵ Tm₁₀²⁴ Yb₁₀²³ Lu₁₀²² Hf₁₀²¹ Ta₁₀²⁰ W₁₀¹⁹ Re₁₀¹⁸ Os₁₀¹⁷ Ir₁₀¹⁶ Pt₁₀¹⁵ Au₁₀¹⁴ Hg₁₀¹³ Tl₁₀¹² Pb₁₀¹¹ Bi₁₀¹⁰ Po₁₀⁹ At₁₀⁸ Rn₁₀⁷ Fr₁₀⁶ Ra₁₀⁵ Ac₁₀⁴ Th₁₀³ Pa₁₀² U₁₀² Np₁₀¹ Pu₁₀¹ Am₁₀⁰ Cm₁₀⁰ Bk₁₀⁰ Cf₁₀⁰ Es₁₀⁰ Fm₁₀⁰ Md₁₀⁰ No₁₀⁰ Lr₁₀⁰ Rf₁₀⁰ Db₁₀⁰ Sg₁₀⁰ Bh₁₀⁰ Hs₁₀⁰ Mt₁₀⁰ Ds₁₀⁰ Rg₁₀⁰ Cn₁₀⁰ Nh₁₀⁰ Fl₁₀⁰ Mc₁₀⁰ Lv₁₀⁰ Ts₁₀⁰ Og₁₀⁰{{actual citation needed}}&amp;lt;!--Pm somewhere near the end?--&amp;gt;&lt;br /&gt;
&lt;br /&gt;
==Transcript==&lt;br /&gt;
{{incomplete transcript|Don't remove this notice too soon.}}&lt;br /&gt;
:[A long panel with a chemical formula trailing off the right side]&lt;br /&gt;
:C&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;76&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; H&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;80&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; Ac&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;67&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; Ag&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;69&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; Al&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;75&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; Am&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;26&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; Ar&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;75&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; As&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;70&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; At&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;47&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; Au&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;69&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; B&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;71&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; Ba&amp;lt;sub&amp;gt;10&amp;lt;sup&amp;gt;70&amp;lt;/sup&amp;gt;&amp;lt;/sub&amp;gt; Be&lt;br /&gt;
:[Caption below the panel:] The approximate chemical formula for the universe&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
{{comic discussion}}&amp;lt;noinclude&amp;gt;&lt;br /&gt;
[[Category:Chemistry]]&lt;br /&gt;
[[Category:Cosmology]]&lt;/div&gt;</summary>
		<author><name>2600:6C56:7800:11BB:B5D1:A120:F5A7:F8AF</name></author>	</entry>

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