+
+## Isomers
+
+* **Structural isomers** - same molecular formula, different arrangement
+* **Stereoisomers** - same structural configuration, different orientation
+ * **Opotical isomers** - chiral centre, 4 groups bonded to C, non-superimposable mirror image
+ * **Geometric isomers** - \ce{C=C} double bond, 2 groups bonded to carbon atoms
+ + **Cis** - same horizontal plane
+ + **Trans** - diagonal
+
+\setlength\tabcolsep{1cm}
+\begin{tabularx}{\textwidth}{cc}
+ cis & trans \\
+ \chemfig{[:60]{\text{\color{blue}R$^\prime$}}-C(-[:120]{\text{\color{red}R}})=[0]C(-[:-60]{\text{\color{blue}R$^\prime$}})-[:60]{\text{\color{red}R}}} &
+ \chemfig{[:60]{\text{\color{blue}R$^\prime$}}-C(-[:120]{\text{\color{red}R}})=[0]C(-[:-60]{\text{\color{red}R}})-[:60]{\text{\color{blue}R$^\prime$}}}
+\end{tabularx}
+