The publication of the periodic table is a milestone in the field of chemistry. Its guiding role and importance in the study and research of chemistry, especially inorganic chemistry, have been widely recognized. In this paper, the educational function and development of the periodic table in inorganic chemistry were discussed. We proposed that more attention should be paid on the organic combination of chemical history and chemical education. We all look forward to the future development of the periodic table.
The periodic system of elements had been individually discovered by German chemist Julius Lothar Meyer and Russian chemist Dmitri Ivanovich Mendeleev during almost the same period of time, who both received the Davy Medal of the Royal Society. However, the contribution of Meyer on the periodic system of elements has not attracted enough attention. On the occasion of the International Year of the Periodic Table of the Elements, the author writes this article to describe Meyer's lifetime and his contribution to chemistry. The present article is dedicated to Meyer, a great pioneer in the history of chemistry.
In this paper, the electronic arrangement of the elements in the d block, instability of the highest valence state of the nonmetals in the fourth period, inert pair effect, similarity and secondary periodicity of the fifth and sixth periodic heavy transition elements, and periodic anomalies of the arrangement of Group Ⅲ elements are introduced in detail with necessary discussions. However, the well-known uncertainty about the position of hydrogen in the periodic table and the particularity of elemental properties of the second period are not within the scope of this article.
Atomic weight is one of the fundamental scientific concepts. "The IUPAC Commission on the Isotopic Abundances and Atomic Weights" revises and releases atomic weights of the elements every two years. Since 2009, IUPAC announced that the atomic weights of some elements are no longer constants of nature, and the standard atomic weights of these elements span an interval. For the convenience of users, a single value is also provided for these elements, which is called "conventional atomic weight". What is the standard atomic weight? What is a conventional atomic weight? Why do the atomic weights of some elements span an interval? According to the characteristics of atomic weight values, how many classes can the elements be divided into? After introducing the characteristics of atomic weights in the latest periodic table of the elements, this article briefly deals with the history of atomic weight determination, the development of the standard of the unified atomic mass unit, and then discusses the revision and changes of atomic weights.
Hydrogen (H2), the smallest molecule and the lightest gas in nature, plays a vital role in our lives. Hydrogen has remarkable preventive and therapeutic effects on various diseases of the human body. It is an important industrial raw material and the most promising clean energy. In this paper, the discovery history of hydrogen, its role in medicine and synthetic chemistry are described.
Hydrogen is the most popular element in the universe. Its chemical properties at ambient condition and extreme conditions like high/low temperature and high pressure are critical to human beings and the universe. Under high pressure, hydrogen is very active and mobile, and the hydrogen-rich materials often show high-temperature superconductivity. In this paper, the author introduced the chemistry of hydrogen that he witnessed, experienced and developed in recent years.
Boron has shown great importance as a metalloid and is closely concerned with human life. The introduction of boron into organic molecules has deeply revolutionized the ability of creating new substances. With the explosive development of organoboron chemistry, considerable attentions have been drawn into this area. This article mainly introduces the development and structure of boron, the definition and characteristics of 1, 2-migration for organoboron compounds together with their specific reaction examples.
Natural products (the secondary metabolites) are the gifts from mother nature to human beings. Because of their complex skeletons and promising pharmaceutical values, structural identification and chemical synthesis of natural products have drawn much attention from synthetic community. Although remarkable achievements have been made in the total synthesis of natural products, there still remain significant challenges concerning long synthetic route, low yield and the lack of selectivity in chemical synthesis. Nature is the best chemist, and it uses various enzymes as catalysts to efficiently synthesize natural products. Exploring the mystery of how nature produces complex and diverse natural products at the genetic level not only provides inspiration for the further development of organic synthesis, but also lays the foundation for the vast utilization of effective enzymes to produce medicine and functional material for humans.
Nitrogen is the main component of air and an important element for various organic compounds. Nitrogen-containing molecules are indispensable to both life and industry. It is still a long-term task for chemists to develop energy-saving and efficient nitrogen fixation methods. Nitrogen oxide and nitrogen dioxide are notorious molecules causing air pollution. Controlling the emission of nitrogen oxides is an important way to control air pollution. Nitrogen-containing biomolecules such as amino acids and proteins are vital nutrient and executors for numerous life events. Other synthetic nitrogen-containing polymers, like Nylon, are important and useful materials in our daily life.
Palladium has played an essential role in human life since its discovery. In this text, the comprehensive applications of palladium are introduced, followed by the cutting-edge scientific researches on the design, synthesis and catalytic mechanism of palladium nanocatalysts.
Photosynthesis is the most important synthetic reaction in nature, the O2-evolution center of which contains the key Mn-O-Ca structure motif. Manganese features earth abundance, low toxicity, rich oxidative states, and unique reactivities, which makes it of great importance and hold huge potentials to achieve new synthesis unavailable by nature. In this paper, the history of manganese-enabled synthetic chemistry and its recent applications in inorganic electrochemistry and organic synthesis are reviewed briefly.
The 4f orbitals of Gd3+ ion are half-filled. This sort of unique electronic structure makes it behave the largest ground spin state and completely quenched orbital momentum over all the possible ions in the periodic table. Based on the introduction of the electronic structure of Gd3+, this paper briefly discusses the application of Gd3+ in the field of nuclear magnetic resonance imaging contrast agent and molecule qubit.
In this paper, the discovery, existing forms and important physiological functions of the element of Selenium (Se) are introduced. The Se applications in bio-chemistry studies are highlighted, which include the detection of living species by Se-containing fluorescent probes, and biomacromolecule studies by Se-containing chemical probes.
Phosphorus is one of the important elements for life, which participates in various biochemical processes. L-Amino acids are the basic structural units of proteins. N-phosphorylation of amino acids makes them be activated and become one kind of "micro activating enzyme", which possesses a variety of biochemical reaction activities, such as peptide formation. Based on the peptide formation reaction of N-phosphoryl amino acids, L-seryl-L-histidine dipeptide (Seryl-histidine dipeptide) is produced and found that it is the smallest functional peptide with a variety of biological enzyme activities. Seryl-histidine dipeptide could be regarded as the original evolution prototype of modern hydrolytic enzyme. This paper reviews the research process from N-phosphoryl amino acids to the discovery of seryl-histidine dipeptide in detail. There are pain, confusion and joy, which fully embodies the charm of scientific exploration.
The author has been engaged in ferrocene chemistry research for a long time. This article describes the research hotspots of ferrocene chemistry and the presentation of ferrocene chemistry in undergraduate teaching. Ferrocene chemistry plays an important role in undergraduate chemistry laboratory courses and teaching reforms. It is a typical example of transforming basic research results into undergraduate teaching content.
It is a vivid platform to demonstrate chemical properties of elements using a periodic table cabinet full of physical samples in the form of elements, compounds and minerals for each element. In combination of appearance of physical samples and chemical principles behind, the periodic table cabinet is an appealing vehicle to display chemical elements and chemistry disciplines.