CONCHEM - simplified version

Chemistry is the study of matter, including what it's made of and how it behaves.

Organic chemistry is a key part of chemistry. It focuses on compounds that contain elements like:

• Carbon (C)

• Hydrogen (H)

• Oxygen (O)

• Nitrogen (N)

• Fluorine (F)

• Chlorine (Cl)

• Bromine (Br)

• Iodine (I)

The Special Role of Carbon

Carbon is the $6^{th}$ element on the periodic table.

It has four outer electrons (valence electrons), which lets it form many bonds.

This makes Carbon the "element of life," as it's the main building block for living things, like in carbohydrates, proteins, fats, and DNA.

Carbon's ability to bond with itself and other non-metals allows for millions of different organic compounds.

Organic vs. Inorganic Compounds

Organic compounds:

• Were once thought to come only from living things.

• Mostly contain carbon and hydrogen.

• Form long, complex chains of molecules.

• Can be found as solids, liquids, or gases.

• Carbon bonds in these compounds are covalent.

Inorganic compounds:

• Come from non-living things (like minerals).

• Usually do not contain carbon.

• Are mostly solids.

• Do not form long, complex chains.

• Can have ionic or covalent bonds.

Important Exception: Some compounds with carbon are considered inorganic if they act like inorganic compounds. Examples include carbon dioxide $(CO_2)$, carbon monoxide $(CO)$, and cyanide compounds.

History of Organic Chemistry

• Ancient Times: People used plant extracts, like willow bark for pain relief (now known to contain acetylsalicylic acid, an aspirin ingredient).

• Early 1800s: Jon Jacob Berzelius first defined organic chemistry. He classified compounds into 'organic' (from living things) and 'inorganic' (from minerals/non-living things). Scientists believed organic compounds only came from living things due to a "vital force."

• 1816: Michael Eugene Chevreul studied fats and alkalis, explaining how soap is made (saponification).

• 1828: Friedrich Wöhler (the "Father of Modern Organic Chemistry") made urea, an organic compound, from an inorganic compound (ammonium cyanate). This showed organic compounds could be made without a "vital force" and led to understanding isomerism (when compounds have the same formula but different structures).

• 1856: William Henry Perkin accidentally found "Perkin's mauve," an organic dye, which boosted interest in organic chemistry.

• Later: Friedrich August Kekulé explained isomerism and developed theories about chemical structures, especially for benzene (a six-carbon ring, where each carbon atom has a hydrogen attached), focusing on how carbon atoms link together and their valence.

• $20^{th}$ Century: Millions of new substances were discovered and made. This led to organic chemistry branching into new fields like polymer chemistry, pharmacology, and petro-chemistry.

Organic chemistry is very important in areas like medicine, engineering, and agriculture.

Functional groups are special parts of molecules that give the molecules their own distinct characteristics and behaviors. They play an important role in forming biological compounds like DNA, proteins, carbohydrates, and fats. For example, the presence of a specific functional group, like a hydroxyl group $(OH)$, makes a molecule an alcohol. Different functional groups cause molecules to react in specific ways.

Some common functional groups include carbonyl, carboxyl, hydroxyl, amino, and halides.

• If an organic compound has a carbonyl group (which is a carbon atom double-bonded to an oxygen atom, written as (C=O)(C=O)), it can be an aldehyde, a carboxylic acid, an ester, or a ketone.

• If an organic compound has oxygen, but not in a (C=O)(C=O) group, it can be an alcohol or an ether.

• Compounds with nitrogen are called amines and amides. Compounds with halogens (like fluorine or chlorine) are called halides.

In chemical formulas for functional groups, we often use 'R' to stand for a part of the molecule that can be an alkyl group or an aryl group.

• An alkyl group is like a simple alkane (like methane or ethane) but missing one hydrogen.

• An aryl group is a ring-shaped molecule (like benzene) also missing one hydrogen.

Alcohol (General Formula ROH)

Alcohols are organic compounds. Think of water (H2O)(H2​O). If you replace one hydrogen with an alkyl group, you get an alcohol. Or, imagine a hydrocarbon chain; if a hydrogen atom on it is replaced by a hydroxyl group (OH)(OH), it's an alcohol.

We name alcohols by changing the end of the parent hydrocarbon's name to '-ol'. For example, methane becomes methanol.

When naming, also consider the number of carbon atoms where the hydroxyl group is attached. The hydroxyl group (OH)(OH) is 'polar', meaning it has a slight positive and negative side. This makes alcohols able to mix well with 'polar' liquids like water.

Methanol is the simplest alcohol. It's also known as methyl alcohol or wood alcohol. Industries use it as a solvent (something that dissolves other things), a pesticide (to kill pests), antifreeze, and as an alternative fuel production.