The Periodic Table of Elements remains one of the greatest accomplishments in science, giving form and order to all the elements that make up the world around us. While the Periodic Table we know and love today took quite a bit of tinkering, like all great things, it came from very humble beginnings. Not that it didn't have a lot of help from a lot of great minds along the way, but the Periodic Table has made quite a journey...
There have always been elements. The existence of elements themselves have been evident since ancient times, but the act of actually calling them elements as a group is a relatively new practice. Elements such as gold, silver, copper, and lead have been known about and used frequently ages and ages ago, along with a handful of others. The first ever actual scientific discovery made by man would not happen until Hennig Brand would make the mistake in 1649. Brand was at the time searching for the Philosopher's Stone, a magical substance which was supposed to turn stones into gold, when he stumbled upon the first scientific discovery of an element: Phosphorus. He had accomplished this by heating up urine until it was split into its base components, and then isolated the Phosphorus gas and solidified it.
Over the next 200 years, chemists worked diligently to discover some 63 elements. As the collection of known elements began to amass, those same chemists started seeing patterns of how the elements reacted, and the bare bones of the Periodic Table of Elements is revealed.
The very first significant groupings of elements came from the chemical prowess of Johann Dobereiner. Between 1817 and 1829, Dobereiner began to place certain elements in groups of three. He first found that Strontium had about the average properties of Calcium and Barium, and grouped these three together accordingly. The Law of Triads was developed. Dobereiner went on to make several more triad groups, including the Halogen triad of Chlorine, Bromine, and Iodine, and the Alkali Metal triad of Lithium, Sodium, and Potassium.
While Dobereiner went on about how nature formed elements in these triad groups, other scientists started to discover that relations between elements went farther beyond just the three, devising lists of 4, 5, and more elements together. However, the thought was ahead of its time. Due to the inaccuracy of many measurements, including atomic weight, the relationship between large element groups could not be exacted.
Speculation on the relationships of elements saw to an advancement of the theory, but the first geometric representation of the elements is accredited to A.E. Beguyer de Chancourtois, circa 1862. Although he had not yet formulated the elements into our familiar table, Chancourtois did arrange the elements into a continuous spiral around a cylinder, separated into 16 parts. When elements were listed around this cylinder in order of their atomic weight, elements with similar properties lined up with each other. While this was a great step forward to the final construction of the Periodic Table, Chancourtois' diagram also contained ions and compounds, so was not entirely a table of elements.
Following both Dobereiner and Chancourtois, John Newlands developed both a logical and graphical representation of the known elements in 1863. Newlands proposed that when he sorted the elements into a table with 8 elements in each row, the resulting columns held elements that had similar properties. He called this the Law of Octaves after the musical effect of a note repeating itself in a higher tone after every 8 notes in a scale. This comparison of music and chemistry was not well received by the scientific community at first, but the theory started to pick up after 1869.
Lothar Meyer and Dmitri Mendeleev would have perhaps made the greatest contribution to the Periodic Table of Elements, if only they hadn't made the same contribution. Meyer and Mendeleev, although they worked independently from each other, each made the same advances in element science at around the same time. Meyer had created a very abbreviated version of the table in 1864 for his textbook. He went on to extend the table to include all known elements at the time, and that version was published in 1870.
Unfortunately, Mendeleev published his extraordinary findings in 1869. Mendeleev not only created a very accurate table (despite many of his atomic weights being wrong, as the era did not have reliable measurements), but he also went one step further than anyone had gone before. He did not try to consolidate all known elements into one complete diagram. He realized that there were yet more elements to be discovered, and left gaps in his table where he imagined those elements to fit. Mendeleev took it one step even further by suggesting what properties those future elements might possess. He went on to correctly predict many elements and their properties, forever leaving his mark on the science of elements.
The twentieth century saw its share of achievements. With the discovery of noble gases and the explanation of why the elements occurred in periods swept the Periodic Table of Elements in a brand new direction. The latest major changes to the Periodic Table were made by Glenn Seaborg. He first discovered Plutonium in 1940 and later went to discover the greater part of the Lanthanide series (elements 94-102). This discovery called for both the Actinide and Lanthanide series elements to be moved under the rest of the Periodic Table, instead of between the Alkali Earth and Transition Metals, so that the viewport was not too wide and the table could still be easily read. Seaborg and his team went to discover hundreds of isotopes, and he was awarded the 1951 Nobel Prize in Chemistry. Element 106 (Seaborgium) was named in his honor. Luckily, he had a relatively and universally easy-to-pronounce name, as naming of the elements requires pronunciation to be similar in all languages.