An introduction to the periodic table
The Periodic Table is more than just a list of elements. It was the result of investigations and thought by many notable scientists, most famously the Russian physicist Dmitri Mendeleev. Its clever structure makes it one of the most useful datatables in all of science, providing information on the chemical and physical properties of elements, depending on their position in the table. Hence its ubiquitous place of honour on laboratory walls.
Mendeleev himself (represented above next to an early version of his Periodic Table, published in 1869) famously left some empty spots in his early periodic table for yet undiscovered elements (most notably elements that he named eka-boron (Eb), eka-aluminium (Ea), eka-manganese (Em), and eka-silicon (Es), later to be renamed as scandium, gallium, technetium and germanium upon their discovery) and predicted some of their physical and chemical properties. His predictions were later found to be in close agreement with experimental measurements. The example below compares his prediction with experimental measurements for the element gallium, discovered in 1875. More information on the history of the Periodic Table can be found here.