Periodic Table 1

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". Twenty years after this, French scientist Antoine de Lavoisier wrote what is regarded as the first chemistry textbook. In it, he began the search to classify the elements in a meaningful way. His list of elements contained substances such as oxygen, nitrogen, mercury and zinc but there were also some compounds that he believed to be elements, plus light and heat, which at the time were still believed to be materials rather than forms of energy. His contribution to the periodic table was to classify his list of elements as metals and non metals. Unfortunately, Lavoisier was a nobleman and as a result, during the French Revolution, he was murdered by the revolutionaries - he was guillotined in Paris.

In the 1800s, chemists were regularly finding new elements and they desperately needed a way to organise them to see the patterns that were becoming evident. Many scientists made attempts at this, including a teacher called John Dalton and a French chemist called Alexandre-Emile Beguyer de Chancourtois (what a name!!). A Russian scientist named Dmitri Mendeleev placed the elements in order of atomic mass whereas we now use atomic number, which was unknown at the time. For the story of the periodic table, you need to go to the next quiz ... but hopefully not before you have tried this one and tested your knowledge of how the elements are arranged into the groups of the periodic table!