Natural Sources Of Organic Compounds

 There are three generally accepted sources of organic compounds: 

• carbonized organic matter
• living organisms
• invention/human ingenuity 

Carbonized Organic Matter: Coal, Oil, and Natural Gas

Hundreds of millions of years ago, the organisms that inhabited earth were quite different than those we find here today. Plants were fast growing and lacked the woody tissues associated with the trees that currently dominate the world's productive ecosystems. Giant plants with broccoli-like stems grew rapidly, died, and decayed to form rich organic soils upon which more and more plants grew.

Eventually, thick layers of decomposing organic matter accumulated in much the same way that peat bogs do today. Over time these massive organic layers were buried under sediment, rock, or ice where they were subjected to tremendous pressures. In this way, they were transformed into various types of coal. 

Meanwhile in Earth's prehistoric shallow seas, simple organisms like algae, bacteria and zooplankton thrived. As these tiny organisms died, they formed thick layers of organic matter on the sandy bottoms of these seas. Compression of layer upon layer of this material produced rocks known as shale. Under the tremendous pressures from the layers above, and with the shifting of earths tectonic plates, the organic matter trapped in these rocks was converted to oil and natural gas over millions of years. The oil and gas migrated into porous rocks like sandstones or into large pockets of space located kilometres below the earth's surface. Thus organic matter from the past became today's fossil fuels.

Humans have known about fossil fuels for over 6000 years; however, only during the past 300 years have they been utilized on a large scale. Coal was the first of the fossil fuels to be extracted from the earth on a commercial basis. It was the fuel that drove the steam engines of the industrial revolution in the 18th, 19th, and 20th centuries. 

Through a process called destructive distillation, coal was converted into coke, coal tar, and coal gas. Coke was used in the smelting of ores, coal tar was refined into over 200 different carbon compounds, and coal gas was used for things like street lighting!

Oil emerged as the dominant energy source for transportation in the 20th century. Natural gas is becoming the clean alternative to coal for generating electricity. It is also widely used as home heating and appliance fuel in North America. The economies of the western world are now completely dependent on oil and natural gas.

To some people, the burning of fossil fuels represents a tremendous waste. Not only does this practice contribute to the build up of carbon dioxide in the atmosphere, it also consumes that raw materials needed to make useful substances like plastics. By some estimates, the world will virtually exhaust its supply of oil and natural gas by 2050 - that's within your lifetime!

Nature: Living Organisms

Every living organism is a source of organic compounds. Each species is capable of producing a wide range of compounds, some of which are unique to that single species. The scent of a rose, the taste of a strawberry, and the fuzziness of a peach are the results of biochemical manufacturing processes within living things. Given that there are hundreds of thousands of species on earth, nature represents our most important source of organic compounds.

Humans have extracted and purified thousands of useful compounds from plants and animals. For example, the penicillin used to fight bacterial infections is extracted from a naturally occurring mold. Acetylsalicylic acid, commonly known as aspirin, comes from the bark of a species of willow tree. Vanilla flavouring is extracted from dried beans that come from a species of orchid called Vanilla planifolia. The heart drug digitalis comes from a plant called Digitalis purpurea. The list of examples goes on for volumes of pages. 

Invention

Antibiotics, aspirin, vanilla flavouring, and heart drugs are examples of substances that no longer have to be obtained directly from nature. They are manufactured in laboratories from organic starting materials. Furthermore, experiments in which the chemical structures of naturally occurring substances are modified has produced organic compounds substances that do not exist anywhere in nature.

Each year over 250,000 new chemical compounds are discovered  and many of these are products of scientists' imaginations, exploration, and in some cases - experiments gone wrong! Plastics are excellent examples of substances that are the product of invention - they are not found anywhere in nature.