Carbon atoms are very good at bonding to each other. They can join up in long chains, chains with branches, and rings, and hold other atoms on the hands left over.
Because carbon can build such a huge variety of shapes, there are millions of different carbon compounds, far more than for any other element. They are so many, and so important, that they have their own branch of chemistry: organic chemistry, the chemistry of compounds built from carbon, usually with hydrogen. A few simple carbon compounds, like carbon dioxide, are left out by tradition.
Why "organic"? Chemists once believed these compounds could only be made by living things, by organisms. Then in 1828 a German chemist, Friedrich Wöhler, made urea, a compound found in urine, from non-living starting materials. The old idea began to fall apart, but the name stuck.
Living things really are built on carbon compounds. About 18% of your body's mass is carbon. In you, it is not diamond or graphite: it is bonded to hydrogen, oxygen, nitrogen and other atoms, in proteins, fats, sugars and DNA.
Quick check
That's the end of lesson 1
In this lesson you found out:
- What atoms are made of, and what makes an atom carbon
- Why carbon usually makes four bonds
- How the same carbon atoms make both diamond and graphite
- What "organic" means to a chemist