1. Chemistry types of reactions๏
See: https://mirror.cse.unsw.edu.au/pub/CTAN/macros/latex/contrib/mhchem/mhchem.pdf
The mhchem package makes it easy to write different types of chemical reactions.
1\documentclass[border=5mm]{standalone}
2\usepackage[version=4]{mhchem}
3\begin{document}
4\begin{minipage}{\textwidth}
5\section*{Examples using mhchem}
6
7\begin{enumerate}
8\item Covalent compounds: \ce{H2O}
9\item Ionic compounds: \ce{NaCl}
10\item Hydrates: \ce{CuSO4.5H2O}
11\item Stoichiometry: \ce{2H2 + O2 -> 2H2O}
12\item Acids and bases: \ce{HCl + NaOH -> NaCl + H2O}
13\item Chemical equation: \ce{H2O -> H+ + OH-}
14\item Simple Isotopes: \ce{^{14}C}
15\item Isotopes: \ce{^{227}_{90}Th+}
16\item Reaction arrows: \ce{A ->[H2O] B}
17\item States of matter: \ce{H2O(l) -> H2O(g)}
18\item States of aggregation: \ce{H2(g) + O2(g) -> H2O(l)}
19\item Charges: \ce{SO4^2-}
20\item Charges: \ce{SO4^2- + Ba^2+ -> BaSO4 v}
21\item Oxidation states: \ce{Fe^{3+} + Cr2O7^{2-} -> Fe^{2+} + Cr^{3+}}
22\item Equilibrium arrows: \ce{CO2 + H2O <=> H2CO3}
23\item Equilibrium arrows: \ce{CO2 + H2O <<=> H+ + HCO3-}
24\item Equilibrium: $K = \ce{\frac{[Hg^2+][Hg]}{[Hg2^2+]}}$
25\item Precipitation: \ce{AgCl(s) <=> Ag+ + Cl-}
26\item Acids and bases: \ce{HCl + NaOH -> NaCl + H2O}
27\item Complex ions: \ce{[Cu(NH3)4(H2O)2]^{2+}}
28\item Hydrates: \ce{CuSO4.5H2O}
29\item Organic compounds: \ce{CH3CH2OH}
30\item Polymers: \ce{(C2H4)_n}
31\item Biochemical compounds: \ce{ATP + H2O -> ADP + Pi + H+}
32\item Nuclear reactions: \ce{^{14}_6C -> ^{14}_7N + e- + $\bar{\nu}_e$}
33\item Redox reactions: \ce{Zn + Cu^{2+} -> Zn^{2+} + Cu}
34\item Ionic equations: \ce{Ag+(aq) + Cl-(aq) -> AgCl(s)}
35\item Half-reactions:\\
36Oxidation half-reaction: \ce{Zn -> Zn^{2+} + 2e-} \\
37Reduction half-reaction: \ce{Cu^{2+} + 2e- -> Cu}
38\item Reaction mechanisms:\\
39Step 1: \ce{NO2 + NO3 -> NO + NO2 + O2} \\
40Step 2: \ce{NO + O3 -> NO2 + O2} \\
41Overall reaction: \ce{NO3 + O3 -> NO2 + O2 + O2}
42\end {enumerate}
43\end {minipage}
44\end {document}