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\usepackage[ngerman]{babel}
\usepackage{appendixnumberbeamer}
\usepackage[version=4]{mhchem}

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\title{Biologischer Kohlenstoffkreislauf}
\author{Simon Bruder}

\institute{Christian-von-Bomhard-Schule}
\usepackage{datetime}
\newdate{date}{15}{1}{2020}
\date{\displaydate{date}}

\begin{document}
 \maketitle

 \begin{frame}{Überblick}
  \begin{minipage}{.33\textwidth}
   \Large\center\textbf{Produzenten}
  \end{minipage}\hfill
  \begin{minipage}{.33\textwidth}
   \Large\center\textbf{Konsumenten}
  \end{minipage}\hfill
  \begin{minipage}{.33\textwidth}
   \Large\center\textbf{Destruenten}
  \end{minipage}
 \end{frame}

 \section{Produzenten}
 \begin{frame}{Photosynthese: Assimilation}
  $\ce{6 CO2 + 6 H2O ->[\text{Sonnenlicht}] C6H12O6 + 6 O2}$
 \end{frame}

 \section{Konsumenten und Destruenten}
 \begin{frame}{Zellatmung und Zersetzung: Dissimilation}
  $\ce{C6H12O2 + 6 O2 -> 6 CO2 + 6 H2O}$
 \end{frame}

 \appendix

 \begin{frame}
 \end{frame}
\end{document}