|
About 700 thousand years ago Homo Erectus probably learnt how to use fire. They could not make it, but they could probably keep it burning when they found it. It let them cook their food, keep warm, see in the dark and defend themselves against animals. This was a great step forward. People were probably the first animals to overcome their fear of fire. No doubt it was treated as a magical force, perhaps worshipped as a spirit.
So what is fire? It is the rapid oxidation of a fuel, usually a carbon based molecule. As the atoms rearrange themselves they release energy, previously stored in covalent bonds, as radiation in the form of heat and light. In the process oxygen is consumed and carbon dioxide and water are released. In the diagram we see formaldehyde burning. |
|
|
Useful Links |
