Types of Carbon Compounds

Carbon compounds

Definition of carbon compounds

Compounds that contain carbon as their constituent element

Organic compounds	Inorganic compounds
Compounds originating from living things that contain the carbon element bonded covalently with other elements such as hydrogen, nitrogen, sulphur and phosphorus	Compounds originating from non-living materials such as oxides of carbon, carbonate compounds and cyanide compounds

Hydrocarbon	Non Hydrocarbon
Organic compounds containing only hydrogen and carbon	Organic compounds containing carbon and hydrogen and other elements, such as oxygen, nitrogen, phosphorus or halogens

Examples of hydrocarbons

Examples of non hydrocarbons

Organic compounds	Composition
Protein	Carbon, hydrogen, nitrogen, oxygen
Starch	Carbon, hydrogen, oxygen
Fat	Carbon, hydrogen, oxygen
Alcohol	Carbon, hydrogen, oxygen

Classification of hydrocarbons

Saturated hydrocarbon

Unsaturated hydrocarbon

Hydrocarbons containing only single bonds between carbon atoms

Hydrocarbons containing at least one double bond or triple bond between carbon atoms

Example of structural formula

The main source of hydrocarbons is petroleum or crude oil.
Petroleum is formed from the remains of plants and animals that perished at the bottom of the ocean, millions of years ago.
Petroleum is a mixture of simple or long-chain hydrocarbons.
Petroleum cannot be used before processing.
It needs to be refined into its constituents through a distillation process.
The two stages of oil refining are fractional distillation and cracking.

The fractions of hydrocarbons in petroleum are separated at different temperatures according to the size of the hydrocarbons.
During the fractional distillation process, petroleum is heated and streamed into a distillation tower.
The fractions in petroleum can be separated because each fraction of the hydrocarbons has its own boiling point.
Hydrocarbons with a lower boiling point will vaporise first, and then rise to the top of the tower before condensing and separating.
Hydrocarbons with a higher boiling point are collected at the bottom of the tower and will condense into liquid.
There are two main uses of hydrocarbon compounds derived from fractional distillation:
- As fuels.
- As raw materials for the petrochemical industry.

Process of fractional distillation of petroleum

Cracking is the process of breaking long chain hydrocarbons into smaller hydrocarbons.
In the cracking process, compounds of large hydrocarbon molecules are heated at a high temperature and pressure.
A catalyst such as a mixture of aluminium oxide, \(Al_2O_3\) and silicon(IV) oxide, \(SiO_2\) are usually used to increase the rate of reaction.
Cracking process produces:
- smaller hydrocarbons such as petrol that is used as fuel.
- alkane and alkene hydrocarbons with shorter chains, to be used as raw materials in the manufacturing of polymers, medicines, detergents, solvents, fertilizers and many more useful products.
The demand for smaller-sized hydrocarbons is higher because it combusts easily, and is used as fuel.
The separation of petroleum compounds through fractional distillation cannot meet the high demands of smaller sized hydrocarbons.

Examples of cracking reaction

Example 1

Example 2

\(\downarrow\)

Ethene

Pentane

Example 3

\(C_{10}H_{22} \rightarrow 2C_{5}H_{10} + H_{2}\)

Based on our current rate of usage, scientists predict that most of the petroleum reserves on earth will be exhausted within 100 years.
Therefore, there is a need for proactive and effective steps to produce alternative resources to replace petroleum.
Alternatives to hydrocarbon refer to alternative energy sources other than nonrenewable fossil fuels.
Biomass is organic matter of plants and animals.
It contains latent energy derived from the sun.
These alternative resources are renewable.
Alternative energy sources can be derived from many chemical processes derived from biomass.

Examples of alternative energy sources

Biomass