When it comes to carbon debate arises as to the distinction between organic and inorganic. Normally, organic relates to living matter – anything from an amoeba to an elephant – and inorganic refers to something that is inanimate, without life like for example, a computer keyboard.
Many scientists insist that life is composed of hydrocarbons, and that only those compounds not containing hydrogen or carbon can be termed ‘inorganic’. This is confused because when plants photosynthesize they produce C02 that is considered to be inorganic. It is a matter of perspective – some theorists maintain the ecosphere is ‘alive’ and so C02 in the atmosphere is part of the ecosystem. Others feel that carbon that leaves the organic ‘shell’ crosses over into the inorganic domain.
Carbon monoxide forms when a carbon compound becomes oxidized but there is a lack of oxygen to make a dioxide bonding:
C +0 – CO
If carbon monoxide is exposed to oxygen it produces a blue flame and becomes carbon dioxide.
CO + 0 – C02
Carbon monoxide is harmful to human health. It is produced as a by-product of iron smelting.
Carbon dioxide is a largely inert compound that is given off in huge amounts by the respiratory systems of animals as well burning fossil fuels and organic matter. Plants, algae and cyanobacteria absorb carbon dioxide, sunlight and water during photosynthesis. They do this to produce carbohydrate energy and the waste product oxygen.
Carbon dioxide can be added to water to make carbonic acid (H2C03). This is a weak acid because most of the carbon dioxide won’t react with the water.
H20 + C02 – H2C03
Nature’s way to make carbonic acid is to use the enzyme, carbonic anhydrase.
Carbonates all contain an ion – a C03 molecule with a 2- charge. Thus, it bonds with other elements readily. The process of carbonation is the adding of carbonates to water to make it fizzy.
Various carbonates are found in rocks. The most common is calcium carbonate (CaC03). Also common is the iron ore carbonate – FeC03. The water softener sodium carbonate (Na2C03), and the popular cleaning alkaline potassium carbonate or potash (K2C03) are well-known types of carbonate.
Cyanide consists of a carbon atom triple bonded to a nitrogen atom. This is the cyanide ion that is famous for its danger. In organic chemistry cyanide compounds are called nitriles. Cyanide is found in certain bacteria, fungi and algae as well as in some food items.
The deadly stuff comes from the Andrussow process in which gaseous hydrogen cyanide is produced from methane and ammonia in the presence of oxygen and a platinum catalyst.
2 CH4 + 2 HN3 +3 02 – 2 HCN +6 H20
Carbides are strong and useful materials that are used in several key industrial processes. There are salt like carbides formed from alkali metals and alkaline earths and some group 3 metals. The covalent carbides of silicon carbide (SiC) and boron carbide (B4C) are used in industry because they are hard and refractory. Interstitial carbides such as titanium carbide (TiC) are used to coat metal in cutting tools.
This is not all of the possible carbon compounds and processes that can be associated with inorganic chemistry, but some of the major ones. It is clear to see how well carbon reacts with other elements and compounds and the range of items it produces from carbonated water to poison to metal coating.