Chemistry - Elements and Compounds

Knowing the differences between elements and compounds is essential to your understanding of science - and of chemistry in particular. You will have started to learn about these quite early on in your studies. You will probably have been told about scientists like Lavoisier, Dalton and others who came up with various ideas and lists of elements and compounds - but the story began long before that. The Greeks came up with the idea that everything is made of various combinations of the '4 elements' earth, water, air and fire. They knew about certain metals like gold, copper, tin and iron and believed there was a substance that could be put with a pile of any metal and after two centuries, it would have turned into gold.

Luckily for us, in the Middle East, Muslim scientists started to work more methodically and developed the scientific method as they practiced their alchemy. For many, it was still a search for the incredible substance that would turn base metals into gold but they turned alchemy from an art into a science that we now call chemistry. Not only did they start to identify elements and compounds, they also developed many processes you use in science today like distillation

European scientists picked up on a lot of the words and processes and took understanding forward. Early attempts at devising a periodic table of the elements were bound to fail as only a small proportion of the elements had been discovered. The early definition of an element was a substance that could not be broken down any further. Until the discovery of electricity and the experiments in electrolysis carried out by Humphrey Davy, many compounds could not be broken down. This meant that scientists were sometimes talking about compounds as if they were elements.

Find out what you know about elements and compounds in this quiz, including the differences between them. (It would be useful to have your periodic table handy) ...