---
+geometry: a4paper, margin=2cm
header-includes:
- \usepackage{mhchem}
+- \usepackage{chemfig}
- \usepackage{tabularx}
---
# Organic Chemistry
Large number of compounds due to:
+
- 4 valence pairs
- single / double / triple bonds
- cyclic (ring) structures
- Indicate number of branches with di-, tri- etc.
- Longest unbranched carbon chain includes function group
-
-
## Functional groups
-\begin{tabularx}{\textwidth}{rX}
- Alcohols & \ce{-OH} \\
- Aldehydes & \ce{-CHO} \\
- Ketones & \ce{-CO-} \\
- Carboxylic acids & \ce{-COOH} \\
- Amines & \ce{-NH2} \\
- Amides & \ce{-CONH2} \\
+\setchemfig{atom sep=2em}
+\renewcommand{\arraystretch}{3}
+\begin{tabularx}{0.5\textwidth}{rlX}
+ \hline
+ Alcohols & \ce{-OH} & \chemfig{{\color{blue}R}-OH}\\\hline
+ Esters & \ce{-OCO-} & \chemfig{{\color{blue}R}-C(=[:-30]O)-[:30]O-{\color{blue}R}}\\\hline
+ Aldehydes & \ce{-CHO} & \chemfig{{\color{blue}R}-C(-[:-30]H)=[:30]O}\\\hline
+ Ketones & \ce{-CO-} & \chemfig{C(-[:150]{\color{blue}R})(-[:-150]{\color{blue}R})=O}\\\hline
+ Carboxylic acids & \ce{-COOH} & \chemfig{{\color{blue}R}-C(=[:-30]O)-[:30]O-H}\\\hline
+ Ethers & \ce{-O-} & \chemfig{{\color{blue}R}-[:210]O-[:-30]{\color{blue}R}}\\\hline
+ Amines & \ce{-NH2} & \chemfig{{\color{blue}R}-N(-[:-30]H)(-[:30]H)}\\\hline
+ Amides & \ce{-CONH2} & \chemfig{{\color{blue}R}-[:30]C(=[:90]O)-[:-30]N(-[:30]H)(-[:-30]H)}\\\hline
\end{tabularx}
+
+## 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
+
+\begin{center}\setlength\tabcolsep{1cm}
+\begin{tabularx}{0.5\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}\end{center}
+
+## Reactions
+
+**Cracking** - split moluecules with heat/pressure/catalyst
+
+### Alkanes
+
+- Relatively inert
+- Non-polar solvent
+- Non-soluble in \ce{H2O}
+- Combusts in \ce{O2} (forms \ce{CO2 + H2O})
+- Reacts with halogens (**substitution** of \ce{H})
+
+### Alkenes
+
+- More reactive than alkanes
+- **Addition reactions**: \ce{C=C} bond is broken (energy released)
+- **Addition polymerisation**
+
+### Alcohols
+
+- Can be formed from haloalkane substitution reaction
+- **Oxidation** (combustion)
+- Oxidation state $\propto$ no. of atoms connected to \ce{C}
+- **Substitution** of functional group, e.g. \ce{ROH + NH3 -> RNH2 + H2O}
+- Primary alcohols oxidise to aldehydes then carboxylic acids
+- Secondary alcohols oxidise to ketones
+
+### Carboxylic acids
+
+- Weak acids
+- **Hydrolysis**: \ce{RCOOH + H2O <=> RCOO^{-} + H2O^{+}}
+- Rxn with amines - carboxylic acid + amine $\rightarrow$ ammonium salt $\rightarrow$ amide + water
+
+### Esterification
+
+- **Condensation reactions** (esterification): \ce{RCOOH + R^{$\prime$}OH -> RCOOR^{$\prime$} + H2O}
+- This is reversed by **hydrolysis**: ester + water $\rightarrow$ carboxylic acid + alcohol
+- Polyesters