Bsrgvty

I'm trying to typeset a chemical equation using the mhchem package, and I want to bold just one part of the equation (to emphasize the product, in this case).

If I type cea A + b B -> c textbfC + d D, then that produces a A + b B → c C + d D. That's perfectly fine, of course. But I cannot put any more complex chemical formulas within the textbf command. If I enter, for example, ceNH3(g) + HCl(g) -> textbfNH4Cl(s), ammonium chloride is typeset as NH4Cl(s), without the subscript.

I tried writing the subscript manually (NH_4Cl), but $ceNH3(g) + HCl(g) -> textbfNH_4Cl(s)$ did not work, and instead gave me a bunch of errors (missing $, extra } or forgotten $, missing , and missing ).

I'm pretty new here so I'm not exactly sure how this MWE thing works — I don't have much that works, but as far as I can tell the code I was using to try things out seems to be pretty close to a MWE. Please let me know if I should provide anything else.

documentclassarticle

usepackage[version=4]mhchem

begindocument

cea A + b B -> c C + d D

cea A + b B -> c textbfC + d D

ceNH3(g) + HCl(g) -> textbfNH4Cl(s)

enddocument

An textbf is a hard break inside a ce. What goes inside textbf's argument is not processed by the mhchem package.

This is the way to go.

ceNH3(g) + HCl(g) -> $textbfceNH4Cl$(s)

Use $ to indicate that you want to escape mhchem parsing (mhchem does the correct guessing that textbf and the next belong together, but using $ is much clearer). Then use textbf, then use ce inside.

The $ part (or the textbf for that matter) might interrupt the mhchem flow. The succeeding (s) works fine, here, but you might not be always so lucky (for instance, a $textbf4$ would not be recognized as a number).

Try

• using ce in math mode (this dose change the output when you use a text font that looks different from the math font, or in headings, as commented by @mhchem) and


• using mathbf instead of textbf
  

See this example:

documentclassarticle
usepackage[version=4]mhchem

begindocument
$ceNH3(g) + HCl(g) -> mathbfNH_4Cl(s)$
ceNH3(g) + HCl(g) -> NH_4Cl(s)
enddocument

It works flawlessly with chemformula, with the difference that the indeterminate coefficients should be typeset in math.

documentclassarticle

usepackagechemformula

begindocument

ch$a$ A + $b$ B -> $c$ C + $d$ D

ch$a$ A + $b$ B -> $c$ textbfC + $d$ D

chNH3(g) + HCl(g) -> textbfNH4Cl(s)

enddocument