Common formulae

Every block on this page is rendered at build time by invoking the asciichem gem. Source on the left; MathML output on the right. If you view the page source, you’ll see the same is what you’d type.

Water and simple molecules

Source Rendered

H_2O CO_2 NaCl CH_4

${\mathrm{H}}_2\mathrm{O}\mathrm{C}{\mathrm{O}}_2\mathrm{Na}\mathrm{Cl}\mathrm{C}{\mathrm{H}}_4$

Acids and bases

Source Rendered

HCl H_2SO_4 HNO_3 H_3PO_4 NaOH Ca(OH)_2

$\mathrm{H}\mathrm{Cl}{\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4\mathrm{H}\mathrm{N}{\mathrm{O}}_3{\mathrm{H}}_3\mathrm{P}{\mathrm{O}}_4\mathrm{Na}\mathrm{O}\mathrm{H}\mathrm{Ca}{\left(\mathrm{O}\mathrm{H}\right)}_2$

Ionic compounds

Source Rendered

Na^+ Cl^- SO_4^2- NO_3^- Ca^2+

${\mathrm{Na}}^{+}{\mathrm{Cl}}^{-}\mathrm{S}{\mathrm{O}}_4^{2-}\mathrm{N}{\mathrm{O}}_3^{-}{\mathrm{Ca}}^{2+}$

Isotopes — the headline semantic fix

Source Rendered

^14C ^131I ^238U ^3H

${}^{14}\mathrm{C}{}^{131}\mathrm{I}{}^{238}\mathrm{U}{}^3\mathrm{H}$

The prefix isotope binds to the atom. See Atoms for the full story.

Coordination complexes

Source Rendered

[Fe(CN)_6] [Fe(CN)_6]_3 [PtCl_4]

$\left[\mathrm{Fe}{\left(\mathrm{C}\mathrm{N}\right)}_6\right]{\left[\mathrm{Fe}{\left(\mathrm{C}\mathrm{N}\right)}_6\right]}_3\left[\mathrm{Pt}{\mathrm{Cl}}_4\right]$

Stoichiometric coefficients

Source Rendered

2H_2O 3H_2 C_6H_12O_6

$2{\mathrm{H}}_2\mathrm{O}3{\mathrm{H}}_2{\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6$

Reactions

Source Rendered

2H_2 + O_2 -> 2H_2O N_2 + 3H_2 <=>[Fe][400°C] 2NH_3 CH_4 + 2O_2 -> CO_2 + 2H_2O

$2{\mathrm{H}}_2+{\mathrm{O}}_2\to 2{\mathrm{H}}_2\mathrm{O}{\mathrm{N}}_2+3{\mathrm{H}}_2\underset{\mathrm{Fe}}{\overset{\text{400°C}}{\rightleftharpoons }}2\mathrm{N}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_4+2{\mathrm{O}}_2\to \mathrm{C}{\mathrm{O}}_2+2{\mathrm{H}}_2\mathrm{O}$

Bonds in linear notation

Source Rendered

H-O-H H_2C=CH_2 HC#CH

$\mathrm{H}-\mathrm{O}-\mathrm{H}{\mathrm{H}}_2\mathrm{C}=\mathrm{C}{\mathrm{H}}_2\mathrm{H}\mathrm{C}\equiv \mathrm{C}\mathrm{H}$

Electron configurations

Source Rendered

1s^2 2s^2 2p^6 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10

${\mathrm{1s}}^2 {\mathrm{2s}}^2 {\mathrm{2p}}^6 {\mathrm{1s}}^2 {\mathrm{2s}}^2 {\mathrm{2p}}^6 {\mathrm{3s}}^2 {\mathrm{3p}}^6 {\mathrm{4s}}^2 {\mathrm{3d}}^{10}$

Verify locally

gem install asciichem
asciichem convert -i "2H_2 + O_2 -> 2H_2O" -t mathml
asciichem convert -i "2H_2 + O_2 -> 2H_2O" -t latex
asciichem roundtrip -i "2H_2 + O_2 -> 2H_2O"