顯示表格標題時出現問題

Question

我面臨著有關表格標題的問題。

程式碼如下：

\documentclass[12pt]{report}
\usepackage[utf8]{inputenc}
\usepackage{gensymb}
\usepackage[version=3]{mhchem}
\usepackage{mathtools}
\usepackage{booktabs}
\usepackage{dirtytalk}
\usepackage{amsmath}
\usepackage{float}
\usepackage[bottom]{footmisc}

\renewcommand{\thefootnote}{\alph{footnote}}

\usepackage{graphicx}
\graphicspath{ {images/} }

\begin{document}   


 \begin{table}[htbp]
      \centering
      \caption{Comparison between \ce{H2o} activity coefficients for the following starting conditions: n_{\ce{NH3}}=3 mole, n_{\ce{H2O}}=34.4 mole; T=57\celsius}
        \begin{tabular}{cccc}
        \toprule
        Something & Something & Something & Something \\
        \midrule
        number & number & number & number \\
        number  & number & number & number \\
        number   & number & number & number \\
        number  & number & number &  number \\
        \bottomrule
        \end{tabular}%
      \label{tab:addlabel}%
    \end{table}%
\end{document}

我不明白為什麼表格標題沒有出現......非常感謝！

Answer 1

n_{\ce{NH3}}諸如需要數學模式（ ）之類的東西$...$。我還建議您使用siunitx工具來排版帶有單位的數字。

微量元素：

\documentclass[12pt]{report}
\usepackage[utf8]{inputenc}
\usepackage[version=3]{mhchem}
\usepackage{mathtools}
\usepackage{booktabs}
\usepackage{float}
\usepackage[bottom]{footmisc}
\usepackage{siunitx}

\begin{document}
\begin{table}[htbp]
  \centering
  \caption{Comparison between \ce{H2O} activity coefficients for the following starting conditions: $n_{\ce{NH3}}=\SI{3}{\mole}$, $n_{\ce{H2O}}=\SI{34.4}{\mole}$; $T=\SI{57}{\celsius}$}
    \begin{tabular}{cccc}
    \toprule
    Something & Something & Something & Something \\
    \midrule
    number & number & number & number \\
    number  & number & number & number \\
    number   & number & number & number \\
    number  & number & number &  number \\
    \bottomrule
    \end{tabular}%
  \label{tab:addlabel}%
\end{table}%
\end{document} 

輸出：