Introduction to organic chemistry

Inorganic chemistry deals with inorganic compounds. Those include the oxides, hydroxides, nitrites, sulphates, sulphites, carbonates, and phosphates of metals or ammonium.

Most substances are made of carbon atoms, when you heat dry wood completely the black residue seen is due to the presence of carbon atoms in it. Other organic compounds include dyes, drugs, papers, plastics and textiles.

Some specific properties of sodium chloride (inorganic compound) and hexane (organic compound)

Melting point: Organic compounds have relatively low melting points, like hexane and ethanol are liquid at room temperature. Most inorganic salts, by contrast have high melting points.

Solubility: Most organic compounds are insoluble in water but are soluble in organic liquids.

Density: Most organic liquids are less dense than water and like oil they float on top of water if we attempt to dissolve them.

Flammability: Organic compounds are flammable, some are highly flammable. Some, like gasoline, form explosive mixtures with air and must not be used near an open flame. Inorganic compounds are non-flammable. Some, such as water and sodium bicarbonate, are even used in fighting fires.

Bonding: Properties of organic compounds are related to the fact that they are composed of molecules with covalent bonds. Inorganic compounds are ionic. Water solutions of ionic compounds conduct an electric current, but water solutions of molecular substances, those having covalent bonds, are non-conductors.

Comparison of an organic and inorganic compound:

1. Applied in the food used by human beings and other living organisms. Example: protein, carbohydrates, lipids, all these contain carbon atoms.
2. Applied in fuel industries in the production of fuel. Example: petrol, kerosene, petroleum, benzene ($C_6H_6$), diesel, all these are organic compounds.
3. Applied in the pharmaceutical industries in the drugs, chemical synthesis. Example: erythromycin, tetracycline, panadol, aspirin, etc.
4. Applied in the plastic material production in the industries. Example: plastic bags, trough, sandals, PVC (polyvinylchloride) used in plastic pipes, electrical wires insulators, all these are organic compounds.

There are three main sources of organic compounds.

1. Petroleum and coal: These substances provide compounds which can be used in their simple forms.
2. Living organisms/plants and animals: Glycogen is an example of an organic compound found in animals. Starch and cellulose are organic compounds found in plants.
3. Synthetic organic compounds: Some organic compounds are synthesized, for example nylon and polyesters. Others include synthetic rubber, colours, dyes, fibres such as artificial sisal fibres and synthetic acids, alcohols, ethers and amines.

A crude oil refinery is a group of industrial facilities that turns crude oil and other inputs into finished petroleum products.

A refinery's capacity refers to the maximum amount of crude oil designed to flow into the distillation unit of a refinery, also known as the crude unit.

Crude oil is made up of a mixture of hydrocarbons, and the distillation process aims to separate this crude oil into broad categories of its component hydrocarbons, or "fractions." Crude oil is first heated and then put into a distillation column, also known as a still, where different products boil off and are recovered at different temperatures.

The simplest refineries stop at this point. Although not shown in the simplified diagram below:

This is the process of breaking down complex compounds to form simpler compounds, which are more useful.

1. Thermal cracking: This is the cracking where heat is used to break down complex compounds to form simpler compounds which are more useful.
2. Catalytic cracking: This is the cracking where a catalyst is used to break down complex compounds to form simpler compounds which are more useful.