Organic Chemistry Fundamentals: Carbon-Based Bonding and Isomerism

Definition: the study of carbon-based molecules and how they interact.
Emphasis in lecture: reactions involve movement and redistribution of electrons; bonds are broken and formed between carbon-based molecules.
The recording captures both PowerPoint content and material written on the board.
If pace is fast, don’t worry; the notes are provided to supplement understanding.

Carbon-based life forms on Earth.
Many everyday materials are carbon-based: what we eat, the clothes we wear, drugs, plastics, and other materials.
Although not absolute, ionic species are often classified as inorganic; example: ammonium ion and cyanate ion.
Example ionic species:
- Ammonium: ext{NH}_4^+
- Cyanate: ext{OCN}^- (note: the formal negative charge is placed on the oxygen in this example; resonance can distribute charge)
The other contrasted case shows a molecule with all covalent bonds (no ionic bonds).

In carbon chemistry, different arrangements of the same atoms can lead to different molecules.
Key concept: constitutional isomers (same molecular formula, different connectivity).
Example: for ext{C}2 ext{H}6 ext{O} there are two distinct constitutional isomers:
- Ethanol: ext{CH}3 ext{CH}2 ext{OH}
- Dimethyl ether: ext{CH}3 ext{OCH}3
Both have the same atoms, but bonds connect them differently, giving different properties and reactivities.

Atoms form covalent bonds; nonmetals commonly form covalent bonds.
Typical bonding patterns (for neutral molecules):
- Carbon: usually forms 4 bonds
- Nitrogen: usually forms 3 bonds
- Oxygen: usually forms 2