I am trying to get superscript (i.e. 1st) in the bibliography using ACS style

Question

I wrote a simple organic chemistry lab report example in which I am trying ACS style bibliography. In the reference section, I would like to have "st" in 1st to be superscript, but it's not working. I would greatly appreciate the community's input. Thank you! Here is a minimal working example:

labReport.tex

\documentclass[12pt]{article}
\usepackage{achemso}
\bibliographystyle{achemso}
\usepackage{graphicx}
\usepackage{caption}
\captionsetup{belowskip=10pt,aboveskip=10pt}
\usepackage[a4paper,margin=1in]{geometry}

%Load math package
\usepackage{amsmath}

%Make cell space and scientific notation
\usepackage{longtable, cellspace, booktabs}
\setlength\cellspacetoplimit{4pt}
\setlength\cellspacebottomlimit{4pt}
\usepackage[table]{xcolor}
\usepackage{siunitx}
\sisetup{scientific-notation = true}

%bibliography source
\begin{filecontents}{job.bib}
@BOOK{Reich2007,
  author = {Eike Reich and Anne Schibli},
  title = {High-performance Thin-layer Chromatography for the Analysis of Medicinal Plant},
  year = {2007},
  publisher = {Thieme Georg Verlag},
  address = {New York},
  edition = {1$^{st}$},
}
\end{filecontents}

%Start writing the lab report
\begin{document}

\section{Results}
\subsection{Table}

%Data
\begin{longtable}{ Cr *{6}{l}SS}
  \caption{Distance measurements and computation of Rf}\\
  \toprule
  & Substance & Number & Solvent dist.(mm) & Spot dist.(mm) & {Rf} \\ 
   \midrule
  \endfirsthead
  \multicolumn{5}{c}{Table}\\[1ex]
  \endfoot
  \bottomrule

  \caption*{The Rf values have three significant figures because the smallest number of significant figures used in Rf calculations (i.e. division) is three. The Rf values of acetaminophen and the unknown are the closest.}
  \endlastfoot
  & Caffeine & 1 & 64.0 & 12.0 & 0.188 \\
  & Aspirin & 2 & 64.0 & 60.0 & 0.938 \\ 
  & Acetaminophen & 3 & 64.0 & 41.5 & 0.648 \\
  & Unknown & 110 & 64.0 & 43.0 & 0.672\\
\end{longtable}

\subsection{Calculation example}
\setlength{\jot}{8pt}
\begin{align*}
Rf_{Caffeine} &=  \frac{Spot\: dist.}{Solvent\: dist.}\\
              &=  \frac{12.0\:mm}{64.0\:mm}\\
              &= 0.18\textbf{8}
\end{align*}

\section{Conclusion}
The identity of the unknown substance \#110 is acetaminophen (i.e. solute) based on  examination of Figure 1 and Rf values in Table 1. 
Both the ethyl acetate/acetic acid solvent (i.e. mobile phase) and the TLC's silica gel (i.e. stationary phase) are polar. 
Separation of compounds is based on the competition of the solute and the mobile phase for binding places on the stationary phase \cite{Reich2007}. 
The less polar compound moves further up the TLC plate, resulting in a larger Rf value. 
Therefore, this experiment suggests that caffeine is the most polar of all three compounds, whereas aspirin is the least polar. 
In Figure 1, there is only one spot in each column, suggesting that cross-contamination between capillary tubes was minimal. 
Faint cross-contamination spots may have appeared had the UV light been used in a darker environment.
Another potential source of error is not spotting enough solution onto the TLC plate but there was four clear spots, so it does not seem to have been a problem. 

\bibliography{job}
\end{document}

Answer 1

Apparently, after consulting again achemso's documentation and example "achemso-demo.pdf", the package does not provide such a superscript as ACS's styles do not foresee it. Note, both the demo *.pdf as well as the *.bib provide even an example of an first edition, too. In addition, see that the corresponding entry in the *.bib simply is an integer, not 1st/2nd/3rd, etc. pp.
If the bibstyle were to use such, it would be the task of BibTeX (or biber/BibLaTeX, alternatively) to do such a conversion of format. What you can do is to look up custom-bib that, after passing a number of questions, allows you to generate a bibtex style file that offers such.

Regarding the table, I would recommend to use a model as simple as possible. With a body of only four compounds tested, substitute this by a tabular environment within a table environment. Use a second header line to accommodate "mm" for column three and four, prior to invoking \midrule of booktabs, too. One caption above the table, and the comment marked by your asterisk as part of the body of the report.

While it may be dependent on convention / school to stay with either Rf or with the f as subscript ($R_f$), be advised to keep text within a formula a text and not as (an ensemble of) variable(s). Hence

\begin{equation}
Rf_{\mbox{caffeine}} = \frac{\mbox{spot distance}} {\mbox{front distance}}
\end{equation}

were correct. Back-referencing to siunitx by the same source, expressions like

\begin{equation}
Rf = frac{\SI{12.0}{\milli\meter}}{\SI{64.0}{\milli\meter}}
\end{equation}

are worth more than a thought, too.

Answer 2

I propose, if that is possible, to use biblatex style chem-acs, and a patch to biblatex command \mkbibordinal:

\documentclass[12pt]{article}
\usepackage[utf8]{inputenc}
%\usepackage{achemso}
%\bibliographystyle{achemso}
\usepackage[style=chem-acs]{biblatex}
\usepackage{graphicx}
\usepackage{caption}
\captionsetup{belowskip=10pt,aboveskip=10pt}
\usepackage[a4paper,margin=1in]{geometry}

%Load math package
\usepackage{amsmath}

%Make cell space and scientific notation
\usepackage{longtable, cellspace, booktabs}
\setlength\cellspacetoplimit{4pt}
\setlength\cellspacebottomlimit{4pt}
\usepackage[table]{xcolor}
\usepackage{siunitx}
\sisetup{scientific-notation = true}

%bibliography source
\begin{filecontents}{job.bib}
@BOOK{Reich2007,
  author = {Eike Reich and Anne Schibli},
  title = {High-performance Thin-layer Chromatography for the Analysis of Medicinal Plant},
  year = {2007},
  publisher = {Thieme Georg Verlag},
  address = {New York},
  edition = {1},
}
\end{filecontents}

\addbibresource{job.bib}

\makeatletter
\DefineBibliographyExtras{english}{
  \protected\def\mkbibordinal#1{%
    \begingroup
    \@tempcnta0#1\relax \number\@tempcnta
    \@whilenum\@tempcnta>100\do{\advance\@tempcnta-100\relax}%
    \ifnum\@tempcnta>20
      \@whilenum\@tempcnta>9\do{\advance\@tempcnta-10\relax}%
    \fi
    \ifcase\@tempcnta \textsuperscript{th}\or \textsuperscript{st}\or \textsuperscript{nd}\or \textsuperscript{rd}\else \textsuperscript{th}\fi
    \endgroup}%
}
\makeatother

\begin{document}

\section{Results}
\subsection{Table}

%Data
\begin{longtable}{ Cr *{6}{l}SS}
  \caption{Distance measurements and computation of Rf}\\
  \toprule
    & Substance & Number & Solvent dist.(mm) & Spot dist.(mm) & {Rf} \\
  \midrule
  \endfirsthead
  \multicolumn{5}{c}{Table}\\[1ex]
  \endfoot
  \bottomrule

  \caption*{The Rf values have three significant figures because the smallest number of significant figures used in Rf calculations (i.e. division) is three. The Rf values of acetaminophen and the unknown are the closest.}
  \endlastfoot
    & Caffeine & 1 & 64.0 & 12.0 & 0.188 \\
    & Aspirin & 2 & 64.0 & 60.0 & 0.938 \\
    & Acetaminophen & 3 & 64.0 & 41.5 & 0.648 \\
    & Unknown & 110 & 64.0 & 43.0 & 0.672 \\
\end{longtable}

\subsection{Calculation example}
\setlength{\jot}{8pt}
\begin{align*}
  Rf_{Caffeine} & = \frac{Spot\: dist.}{Solvent\: dist.} \\
                & = \frac{12.0\:mm}{64.0\:mm} \\
                & = 0.18\textbf{8}
\end{align*}

\section{Conclusion}
The identity of the unknown substance \#110 is acetaminophen (i.e. solute) based on examination of Figure 1 and Rf values in Table 1.
Both the ethyl acetate/acetic acid solvent (i.e. mobile phase) and the TLC's silica gel (i.e. stationary phase) are polar.
Separation of compounds is based on the competition of the solute and the mobile phase for binding places on the stationary phase \cite{Reich2007}.
The less polar compound moves further up the TLC plate, resulting in a larger Rf value.
Therefore, this experiment suggests that caffeine is the most polar of all three compounds, whereas aspirin is the least polar.
In Figure 1, there is only one spot in each column, suggesting that cross-contamination between capillary tubes was minimal.
Faint cross-contamination spots may have appeared had the UV light been used in a darker environment.
Another potential source of error is not spotting enough solution onto the TLC plate but there was four clear spots, so it does not seem to have been a problem.

\printbibliography

\end{document} 

Answer 3

You can fool achemso.bst into printing “1^st”, but I strongly discourage it to.

See https://tex.stackexchange.com/a/53614/4427 for a reference to a discussion about the superscripted ordinal suffix, whose resurrection from a well deserved oblivion seems to be due to a well known word processing program that imposes it to its users.

If you type

edition={\firstwithhorriblesuperscript},

in the .bib file and add

\providecommand{\firstwithhorriblesuperscript}{1\textsuperscript{st} }

to your document preamble, you get the expected horrible result: