Numbers immediately after operator subscripted in mhchem environment

Question

The following is the output of this MWE:

\documentclass[12pt]{article}
\usepackage[version=4]{mhchem}
\usepackage{siunitx}
\begin{document}

\ce{a = 2 \times 3}\\
\ce{a = 2 \div 3}\\
\ce{a = 2 \times b}\\
\ce{a = 2 \div b}

\end{document}

Note how the character is subscripted only when the character after theoperator is a number.

How would I prevent the number from being subscripted?

Erh, what exactly are you trying to do here? \ce has a very specific use and a very specific input syntax — daleif, Dec 20 '18 at 09:31
@daleif I'm showing a few stoichiometric calculations. Would you suggest me end the \ce before inputting the numbers? — George Tian, Dec 20 '18 at 09:33

score 2 · Answer 1 · answered Dec 20 '18 at 10:09

Simply preventing the operators from gobbling the space after them by providing an empty argument fixes the problem:

\documentclass[12pt]{article}
\usepackage[version=4]{mhchem}
\usepackage{siunitx}
\begin{document}

\ce{a = 2 \times{} 3}\\
\ce{a = 2 \div{} 3}\\
\ce{a = 2 \times b}\\
\ce{a = 2 \div b}

\end{document}

See also: Space after LaTeX commands

score 2 · Accepted Answer · answered Dec 20 '18 at 10:28

2

I'm not sure why you're using \ce for this: I see no reason for a and b being upright.

You can embed math mode in \ce:

\documentclass[12pt]{article}
\usepackage[version=4]{mhchem}
\usepackage{siunitx}
\begin{document}

\ce{a = $2 \times 3$}\\
\ce{a = $2 \div 3$}\\
\ce{a = $2 \times \ce{b}$}\\
\ce{a = $2 \div \ce{b}$}

\end{document}

On the other hand if the calculations are inside \ce material, I guess

\documentclass[12pt]{article}
\usepackage[version=4]{mhchem}
\usepackage{siunitx}
\begin{document}

\ce{$a = 2 \times 3$}\\
\ce{$a = 2 \div 3$}\\
\ce{$a = 2 \times b$}\\
\ce{$a = 2 \div b$}

\end{document}

is what you're looking for.

answered Dec 20 '18 at 10:28

egreg

1,121,712

Thanks, using $$ within \ce was what I was looking for. – George Tian Dec 20 '18 at 10:45
Why do you use \ce at all? Simply write $a = 2 \times 3$ . – mhchem Dec 22 '18 at 14:57
@mhchem I guess that this is just a short example. – egreg Dec 22 '18 at 15:00

Numbers immediately after operator subscripted in mhchem environment

2 Answers2