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 % Document information
 \title{Chemistry Vocabulary}
 \author{}
-\date{\today}
+\date{}
 
 \begin{document}
 
 \maketitle
 
-\section{Introduction}
-
-% Add your content here
+\section*{Introduction}
 
 \section{Elements and elementary substances}
 
+\subsection{Alkali metals}
+
+\subsection{Alkaline earth metals}
+
+\subsection{Transition metals}
+
+\subsection{Post-transition metals}
+
+\subsection{Metalloids}
+
+\subsection{Halogen}
+
+\subsection{Noble gases}
+
+\subsection{Other Nonmetals}
+
 \section{Acids and bases}
 
 \section{Ions}