# How to write Lewis symbols and structures , balancing chemical equations using LaTeX?

#### Dhamnekar Winod

##### Active member
Hi,

How to draw Lewis diagrams, Lewis symbols , chemical equations in LaTeX?

#### Klaas van Aarsen

##### MHB Seeker
Staff member
Hey @Dhamnekar Winod,

LaTex in general? Or here on MHB?

Either way, we can draw chemical structures with for instance the chemfig package.
Use it in a LaTeX document like this:
LaTeX:
\documentclass{article}
\usepackage{chemfig}
\begin{document}
\chemname{\chemfig{
C(-OH)(-[2]C-OH)(-[6]C-OH)
}}{Glycerol}
\end{document}
Embed it in a TikZ picture to show it on MHB:
\begin{tikzpicture}
%preamble \usepackage{chemfig}
\node {
\chemname{\chemfig{
C(-OH)(-[2]C-OH)(-[6]C-OH)
}}{Glycerol}
};
\end{tikzpicture}
Click on the picture to see the LaTeX code.

I haven't tried to draw Lewis diagrams or symbols with it yet, but I expect that chemfig supports that as well.
Of course there are also other LaTeX packages to draw chemical structures.

Regular chemical formulas can be done with the usual MathJAX on MHB.
Or you can put it in an actual LaTeX document by including the mhchem package.
So we can write for instance:
LaTeX:
\ce{O2 + 2H2 -> 2H2O}
Put it between dollars and it shows up like:
$$\ce{O2 + 2H2 -> 2H2O}$$

Or put it in a LaTex document like:
LaTeX:
\documentclass{article}
\usepackage[version=4]{mhchem}
\begin{document}
\ce{O2 + 2H2 -> 2H2O}
\end{document}

Last edited: