Organic chemistry

If you're out shopping, you will find many items with the word "organic" on the label. In this context, "organic" is used to make a product sound more 'natural'. In chemistry however, "organic" has a different, and more precise meaning. Originally, scientists used it when studying substances found in living things - the chemistry of organisms. Today we say that organic chemistry is the study of carbon-based compounds, whether they're produced in nature or not.

All living things are mostly made up of organic compounds like proteins, fats, and carbohydrates. We fuel our cars with organic compounds made from oil. Almost all medicines are organic compounds. And so are all the plastic materials, and the synthetic fibres that we use in our clothes. Until the 1800s, organic compounds were thought to only occur naturally.

Today we create many organic substances in the laboratory and in factories. There are over ten million compounds that we know of, and about 90 % of them contain carbon. To understand how organic compounds are structured, we start by looking at a chain of carbon atoms, surrounded by hydrogen atoms. This can be a straight chain, a branched chain or even a loop. It is the length of the carbon chain that determines the name the molecule.

Here for instance is the compound pentane. The first part of the name -- pent - comes from the length of the carbon chain. Five carbons in a row always have the first name "Pent". The second part of the name tells us what is attached to the carbon atoms. If there are only hydrogen atoms, the name of the compound will end with "-ane". "Pent Ane".

The last part of the name is like a surname, showing which family - or class of compounds - the organic molecule belongs to. If we replace one of the hydrogen atoms with another group of atoms -- another functional group -- the molecule gets a different surname. Like this substance, "Pent Anol", which belongs to the family of alcohols. The name still starts with "pent" since it has a chain of five carbon atoms. The ending "-anol" is the family name of all the alcohols.

Here's another member of the alcohol family: "Eth Anol". "Anol" shows that it is an alcohol. The first part of the name "Eth", shows that it has two carbon atoms in its carbon chain. When studying organic chemistry, you need to learn which first name corresponds to which number of carbon atoms... ... and also the family names of some of the classes of compounds. When you know these, you can put together any first name...

With any family name... To get the complete name of the organic compound.