\ce{H_2O}
\ce{Sb_2O_3}
\ce{H^+}
\ce{CrO^{2-}_4}
\ce{ArCl^-_2}
\ce{[ArCl_2]^-}
\ce{Y^{99+}}
\ce{H_{2(aq)}
\ce{NO^-_3}
\ce{(NH_4)_2S}
\ce{2H_2O}
\ce{\tfrac{1}{2}H_2O}
\ce{^{227}_{90}Th^+}


\ce{KCr(SO_4)_2\cdot 12H_2O}
\ce{[Cd\lbrace SC(NH_2)_2\rbrace _2]\cdot [Cr(SCN)_4(NH_3)_2]_2}
\ce{RNO_2^{-\cdot}}
\ce{\mu\hyphen Cl}


\ce{C_6H_5\bond{-}CHO}
\ce{X\bond{=}Y\bond{#}Z}
\ce{A\sbond B\dbond C\tbond D}
\ce{A\bond{-}B\bond{=}C\bond{#}D}
\ce{A\bond{~}B\bond{~-}C}
\ce{A\bond{~=}B\bond{~--}C\bond{-~-}D}
\ce{A\bond{...}B\bond{....}C}
\ce{A\bond{->}B\bond{<-}C}
\ce{Fe(CN)_{\frac{6}{2}}


x\ce{\Na(NH_4)HPO_4\overset{\Delta}{\to}(NaPO_3)}{}_x+x\ce{NH_3}\uparrow+x\ce{H_2O}
\ce{CO_2+C \-> 2CO}
\ce{CO_2+C \<- 2CO}
\ce{CO_2+C \<=> 2CO}
\ce{H^++OH^- \<=>> H_2O}
\ce{CO_2+C\xrightarrow{\text{above}}2CO
\ce{CO_2+C\xrightarrow[\text{below}]{\text{above}}2CO
\ce{A\xrightarrow{+H_2O}B}
\ce{SO^{2-}_4+Ba^{2+}\toBaSO_4\downarrow}


\ce{Zn^{2+}\xrightleftharpoons[+2H^+]{+2OH^-}\underset{\text{amphoteres Hydroxid}}{Zn(OH)_2\downarrow}\xrightleftharpoons[+2H^+]{+2OH^-}}\underset{\text{Hydroxozikat}}{[Zn(OH)_4]^{2-}}
K=\ce{\frac{[Hg^{2+}][Hg]}{[Hg_2^{2+}]}}
\ce{Hg^{2+}\overset{I^-}{\to}\underset{\text{red}}{HgI_2}}\overset{I^-}{\to}\underset{\text{red}}{[HgI^{II}I_4]^{2-}}