While I was wondering in Nottingham, I came across this book and I bought it straight away. This is where my passion from chemistry started from: by studying the periodic table, the “rational” collection of all the elements on earth. If you want to buy the same book please click here.
What’s the periodic table and why it is so important to the chemistry community? The periodic table displays all the element on earth ordered by their atomic numbers and every element is displayed by using their symbols. The atomic number is the number of protons in the nucleus. The chemical symbol is usually derived from the Greek or Latin name of the element. For example, the name Hydrogen, symbol H, has Greek origin and means able to produce water. Potassium has chemical symbol K. K stands for kalium which means ashes. In fact, potassium is very abundant in ashed and this why the chemical element is named like this.
Why do we arrange elements in rows and columns and why do we call it the periodic table? Back in 1800, chemists understood that some of the elements known back showed similar chemical properties and these elements could have been arranged in groups. The scientific community has traditionally been always conservative and the idea of displaying elements in a simple table was heavily criticised at the start. However, in 1863, Dimitri Mendeleev made a formal presentation to the Russian Chemical Society, titled The Dependence between the Properties of the Atomic Weights of the Elements, which described elements according to both atomic weight and valence. So, in simple words, if we order chemical elements according to their atomic weights, we observe that chemical properties repeat in a systematic manner. This repetition is called periodicity and elements with the same chemical properties are arranged in the same column, which we call group. What’s the meaning of the rows? In 1900, new the new theories about quantum-mechanics help in rationalising the structure of atoms. In a nutshell, atoms are made of electrons, protons and neutrons. Electrons are arranged in different energetic levels. The first level accommodates only 2 electrons and this is why we see only two elements in the first row or period. The second energetic level fits eight electrons, and this is why we have 8 elements in the second period and so on.
Mendeleev published the periodic table of all known elements in 1800. Most of the elements were yet to be discovered then. However, Mendeleev predicted the properties of several missing elements. He was proven to be correct when Gallium and Germanium were found as they fit perfectly into the two of the missing spaces.
The periodic table is also the name of one of his most famous books of Primo Levi also regarded as the manifesto of science communication by the chemistry world. Primo Levi was an Italian writer, chemistry and also a Jew during the second world war. He was kept in Auschwitz where he managed to save his lifeby working as a chemist in the camp chemistry lab. He wrote the book to tell his story and related every element to a specific episode of his life. My favorite chapter is Vanadium where he tells the story of this German lab supervisor, what we call PI nowadays, he came across with many years after he escaped the camp.