When were elements discovered?
Thursday 12 April 2018
There are many links on the IB chemistry syllabus that relate to when elements were discovered. Probably the most important one is Topic 3.1 The periodic table. One of the reasons why Mendeleyev was able to come up with his Periodic Table in 1869 was that by then some 63 elements were known and characterised. Compare this with just 100 years earlier when only 19 elements were known. Topic A.2 Metals and ICP spectroscopy in the Options relates the ease of extraction of metals to their position in the activity or electrochemical series. These two series (which are covered in Topics 9.1 Oxidation & reduction and 19.1 Electrochemical cells (AHL) respectively) also tend to mirror when metals were first discovered since the least reactive metals such as gold, silver, copper and lead have been known for more than two thousand years whereas the most reactive metals needed the discovery of electrolysis in the early nineteenth century before they could be isolated from their ores.
Jamie Gallagher has produced a really nice 99 second video which shows what the Periodic Table of the elements for each year of the past 300 years would have looked like if contained just the then known elements. It really does help to put much of chemistry into perspective.