Twenty years after this, French scientist Antoine de Lavoisier wrote what is regarded as the first chemistry textbook. In the middle of the seventeenth century, Irish scientist Robert Boyle came up with a definition of an element that lasted until the the discovery of sub-atomic particles, he said that "an element is a substance that could not be broken down into a simpler substance by a chemical reaction". It would have been a very difficult task anyway because some of the substances they discovered were compounds only a few of them were what we now know are true elements. They managed to discover some of the materials that made up the world around them, however, since they were actually looking for a mythical substance that would turn base metals into gold (the Philosopher's Stone), they never actually thought of devising a periodic table. It's a long way from our current model of over 100 elements arranged into 8 groups but there are some people who stiill believe this mystical idea! It took 1,000 years before the alchemists of Islam started to carry out experiments systematically.
They believed that everything was made from four elements - fire, air, earth and water.
The ancient Greek philosophers knew very little about science, however, that didn't stop them coming up with ideas to help to explain the world around them. In this quiz we take a look at how the periodic table is organised into groups and periods, and also at some of the information we can get about elements from their position in the table. For GCSE Chemistry it is vital that students have a good understanding of the periodic table.
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