\starttext

\chemical{2H_2,+,O_2,->,2H_2O}

\ruledhbox\bgroup
\startformula
    \chemical{2H_2}{}{}
\stopformula
\egroup

\ruledhbox\bgroup
\startformula
    \inlinechemical{2H_2,+,O_2,->,2H_2O}
\stopformula
\egroup

\ruledhbox\bgroup
\startchemicalformula
    \chemical{S}
    \chemical{+}
    \chemical{O_2}
    \chemical{GIVES}{violent}
    \chemical{\+{4}{S}\-{2}{O_2}}
\stopchemicalformula
\egroup

\ruledhbox\bgroup
\startchemicalformula
    \chemical{S}
    \chemical{+}
    \chemical{O_2}
    \chemical{GIVES}
    \chemical{\+{4}{S}\-{2}{O_2}}
\stopchemicalformula
\egroup

\ruledhbox\bgroup
\startchemicalformula
    \chemical{S}
    \chemical{+}
    \chemical{O_2}
    \chemical{GIVES}{boven}{onder}
    \chemical{SO_2}
\stopchemicalformula
\egroup

\ruledhbox\bgroup
\startchemicalformula
    \chemical{S}
    \chemical{+}
    \chemical{O_2}
    \chemical{EQUILIBRIUM}{boven}{onder}
    \chemical{SO_2}
\stopchemicalformula
\egroup

\ruledhbox\bgroup
\startchemicalformula
    \chemical{S}
    \chemical{+}
    \chemical{O_2}
    \chemical{MESOMERIC}{boven}{onder}
    \chemical{SO_2}
\stopchemicalformula
\egroup

\stoptext
