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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

The supposed "chemical formula for the universe" 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 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.

These numbers are large, but they are not nameless. Using the short scale, these numbers can be described as:

• C_10⁷⁶ - Ten quattuorvigintillion carbon atoms
• H_10⁸⁰ - One hundred quinvigintillion hydrogen atoms
• Ac_10⁶⁷ - Ten unvigintillion actinium atoms
• Ag_10⁶⁹ - One duovigintillion silver atoms
• Al_10⁷⁵ - One quattuorvigintillion aluminium atoms
• Am_10²⁶ - One hundred septillion americium atoms
• Ar_10⁷⁵ - One quattuorvigintillion argon atoms
• As_10⁷⁰ - Ten duovigintillion arsenic atoms
• At_10⁴⁷ - One hundred quattuordecillion astatine atoms
• Au_10⁶⁹ - One duovigintillion gold atoms
• B_10⁷¹ - One hundred duovigintillion boron atoms
• Ba_10⁷⁰ - Ten duovigintillion barium atoms
• Be - An unknown quantity of beryllium atoms

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 formed later as a result of stellar nucleosynthesis, up to atomic mass 56. Still more massive nuclei have been 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 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 "formula". There are fewer atoms of americium in the entire universe than there are molecules of liquid water in 3.0 L.

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 C11H15NO2 has 302 registered isomers. Many of them are NOT good to eat.

Transcript

[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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