# Chemical equation with heat of formation

I'm new to Latex and I'm having some trouble with a simple chemical equation. I have the following code:

\documentclass{article}
\usepackage[version=3]{mhchem} % Package for chemical equation typesetting
\usepackage{amssymb}

\begin{document}
$$\ce{N2(g) + 3H2(g) -> 2NH3(g)}}$$
$\Delta H_{\mathrm{f}}^\circ = \SI{-92.5}{kJ}$
\end{document}


This prints everything that I need, but on separate lines. I would just like the heat of formation (deltaH=-92.5kj) to be inline with the equation. I've tried multiple approaches, but keep getting stuck. I haven't seen this discussed on TEX or elsewhere.

-
Welcome to TeX.sx! –  clemens Mar 3 '14 at 19:01
@Eric Morgan, if one of the solutions below has answered your question, would you consider marking it as solved so other users with the same query can jump to the solution. –  Leeser Mar 21 '14 at 12:17

You can simply write it inside the equation and maybe add some horizontal space between with \quad or \qquad:

\documentclass{article}
\usepackage[version=3]{mhchem} % Package for chemical equation typesetting
\usepackage{amssymb}
\usepackage{siunitx}
\begin{document}

$$\ce{N2(g) + 3H2(g) -> 2NH3(g)} \qquad \Delta H_{\mathrm{f}}^\circ = \SI{-92.5}{kJ}$$

\end{document}


An alternative using chemmacros:

\documentclass{article}

\usepackage{chemmacros}

\begin{document}

$$\ch{N2\gas{} + 3 H2\gas{} -> 2 NH3\gas} \qquad \Enthalpy(f){-92.5}$$

\end{document}


For a non-molar heat of formation it would let you easily define a command \formation:

\documentclass{article}

\usepackage{chemmacros}
\NewChemState\formation[subscript=f]{H}{\kilo\joule}

\begin{document}

$$\ch{N2\gas{} + 3 H2\gas{} -> 2 NH3\gas} \qquad \formation{-92.5}$$

\end{document}


There are a number of options for customization (e.g. regarding the position of the subscript).

-

You can use the align environment from »amsmath«. You only need to use \cee for the chemical part of the equation.

\documentclass[11pt]{article}
\usepackage[T1]{fontenc}
\usepackage[version=3]{mhchem} % Package for chemical equation typesetting
\usepackage{amsmath}
\usepackage{siunitx}

\begin{document}
\begin{align}
\cee{N2(g) + 3H2(g) &-> 2NH3(g)} & \Delta H_{\text{f}}^\circ = \SI{-92.5}{\kilo\joule}
\end{align}
\end{document}


-
Thanks, @Thorsten that worked perfectly. I guess I had the wrong combination of packages. –  Eric Morgan Mar 3 '14 at 19:08

Use the chemmacros package. Then simply use the command \Enthalpy(f){-92.5}

-
Cgnieder's answer is more complete...and addresses the question fully –  Leeser Mar 3 '14 at 20:00