Matter and the Periodic Table of Elements

About 100 different kinds of atoms make up all kinds of matter, and they are classified in a table—the Periodic Table of Elements—according to their construction. The center of any atom is a nucleus containing protons and neutrons. The protons have a positive charge and the neutrons are neutral so the nucleus is positively charged. Electrons, equal in number but opposite in charge to the protons, move around the nucleus in orbits. You might think of an atom like a solar system. The nucleus acts like the sun the electrons orbit the nucleus like the planets circle the sun. 

Most of the elements on the Periodic Table of Elements exist as solids at standard temperature and pressure. Much of the matter that you encounter on a daily basis is also found in the solid phase. Probably the two most interesting things about solids are that they are mostly made up of empty space and that even their molecules are in constant motion. 

Looking at periodic tables from different times and produced in different countries reveals a long history of scientific and political struggle. Even today, periodic tables demonstrate the creator s position regarding the control of chemistry by a governing body through its decision whether to use the IUPAC system or the names declared by the discoverers. Despite the various controversies, the periodic table of elements has become a standardized tool for education and research. It can be found as giant wall charts in classrooms and on wallet-size laminated plastic charts, and there are interactive versions on the Internet. It seems that the question of what the elements are and how they work has been answered. As far as everyday life is concerned, the elements listed on the periodic table really do constitute the matter that makes up the world around us, at least to element 92. 

Element The most fundamental form of matter at a chemical level. The great range of ideas about elements and what substances should be considered elements has driven chemical research for much of the history of civilization. Early thinkers generally assumed that there was a small number of elements (from 1 to 5), but today we recognize about 110 naturally occurring and artificial elements found on the Periodic Table of Elements. 

The sixth in the periodic table of elements is, at the same time, among the most important ones. With about 180 ppm, carbon is only 17th on the list of terrestrial elements frequency, situated even after barium or sulfur-for comparison, the second-most frequent element, silicon, is about 1300 times as abundant as carbon. Still the latter is essential for the assembly of all organic matter. It is predestined for this central role especially due to its mid position in the periodic system and its associated ability to form stable substances with more electropositive and more electronegative reaction partners. Yet in the present text the organic chemistry resulting from these various bonding possibilities will only be mentioned if it is employed to modify carbon materials or, to put it in other words, the element itself as a material will be in the focus. 

We will first study the particles that make up atoms, aud the basic structure of atoms, along with some history and the organization of the periodic table of elements. Then we will take a look at the quantum mechanical theory of atoms and see how this theory describes the arrangement of the electrons in atoms. Current atomic theory is by no means complete. Even so, it is a powerful tool that helps us describe the boudiug forces that hold atoms together to form the vast array of matter that makes up the universe. 

From the time that they first used tools and tried to change their environment in other ways, humans have known that the world is made up of basic materials. Thousands of years later, ancient civilizations agreed on a few main elements such as fire and water that they thought were the building blocks of everything on Earth. The modern list of elements and their properties was discovered only in the past few hundred years. The simple yet elegant family tree of all matter, the periodic table of the elements, was finally uncovered in the nineteenth century. The building blocks of elements themselves—the reason that the periodic table is periodic—were not known until the early twentieth century, when subatomic particles were finally revealed. The most recent elements added to the periodic table did not exist at all until scientists identified them in the debris of war and created them from scratch in the middle of the twentieth century. 

In Part 1, you will use the skills and content you learned in Unit 1, Matter and Chemical Bonding. In particular, you will be applying your knowledge of elements and the periodic table,... 

When Mendel eff announced the Periodic Table of the Elements, he frankly stated, It has been evolved independently of any conception as to the nature of the elements. It does not in the least originate in the idea of a unique matter and it has no historical connection with that relic of the torments of classical thought/ He was alluding to the ancient idea of the unity of all matter. Plato had said Matter is one." Sporadically, this idea of a primordial substance from which everything else originated had been enunciated by philosophers and pseudo-scientists. The world paid little attention to their abstract conclusions. 

The Pauli exclusion principle is a quantum mechanical principle formulated by Wolfgang Pauli in 1925, which states that no two identical fermions may occupy the same quantum state simultaneously. It is one of tire most important principles in physics, primarily because the three types of particles from which ordinary matter is made—electrons, protons, and neutrons—are all subject to it. The Pauli exclusion principle underlies many of the characteristic properties of matter, from the large-scale stability of matter to the existence of the periodic table of the elements. 

When these elements were eventually discovered, and because his system agreed with one developed independently by the German chemist Lothar Meyer in 1864, Mendeleev achieved widespread fame. The Periodic Table of the Elements provided a unifying system for classifying and understanding the elements and their function in the composition of matter. 

The periodic table of the elements is a subset of a more general periodic function that relates all natural nuclides in terms of integer numbers of protons and neutrons, the subject of elementary number theory. The entire structure is reproduced in terms of Farey sequences and Ford circles. The periodicity arises from closure of the function that relates nuclear stability to isotopic composition and nucleon number. It is closed in two dimensions with involution that relates matter to antimatter and explains nuclear stability and electronic configuration in terms of space-time curvature. The variability of electronic structure predicts a non-Doppler redshift in galactic and quasar light, not taken into account in standard cosmology. 

In 1923 Bohr wrote to Pauli (figure 7.4), asking him to try to bring order to the increasingly complicated situation in atomic physics and to attempt to save the quantum numbers. Pauli responded with two papers that seemed to clarify matters, and in the process he developed his exclusion principle, which has become one of the central pillars of modem physics. Once again, the motivation for this work was partly an attempt to explain the periodic table of the elements. 

The periodic table of the elements is one of the most powerful icons in science a single document that captures the essence of chemistry in an elegant pattern. Indeed, nothing quite like it exists in biology or physics, or any other branch of science, for that matter. One sees periodic tables everywhere in industrial labs, workshops, academic labs, and of course, lecture halls. 

The purest form of matter is an element, which is composed of identical components called atoms. Elements cannot be broken down or changed by chemical or physical means. The periodic table (chemical element chart) lists information about all known elements, including atomic mass, symbol, atomic number, and boiling point. 

In September 1936, a Mendeleev Congress was held in Moscow, organized by the Academy of Sciences to celebrate the 100th birthday of the discoverer of the Periodic Table of the Elements. By invitation of the Academy of Sciences, the then-recent winners of the Nobel Prize, Irene Joliot-Curie (12 September 1897-17 March 1956) and Frederic Joliot-Curie (19 March 1900-14 August 1958) were the guests of honor. On September 29, 1936, Frederic presented his lecture "The Structure of Matter and Artificial Radioactivity" at the Physical Faculty of MSU. The famous Soviet scientists S. I. Vavilov, N. D. Zelinskiy, L. I. Mandelshtam, A. Y. Fersman, and Frumkin were all present. The Joliot-Curie couple also visited the Karpov Institute, where Frumkin showed them around (Photo 4.18). 

---