Chemistry

This article focuses on explaining why lithium is known as the "star of energy". It introduces that although lithium is a "high-energy metal" with high heat of combustion, its reputation mainly stems from its role in the field of atomic energy. Lithium's isotopes can be fissioned by neutron bombardment to produce tritium, which is necessary for nuclear fusion and is used as fuel for hydrogen bombs. At the same time, lithium can be used to make high-performance lithium metal batteries and lithium-ion batteries to power various devices. It can also be used to make ultra-light alloys for aerospace applications to save energy, making it a "big star" in the energy field.

This article focuses on the question of "are there metals lighter than water?" It introduces the applications and characteristics of light alloys, explains that weight and lightness are relative, and points out that the three metals lithium, sodium, and potassium in the periodic table have a density lower than that of water. Among them, lithium is the metal with the lowest density. It also describes the different storage methods of these three chemically active metals.

This article focuses on why carbon can "transform into various forms", and introduces that carbon atoms, due to their strong "chemical bonding" ability, can form various allotropic forms of carbon with different structures and properties, such as diamond and graphite. Different single-element carbons can transform into each other under specific conditions. It also explains the structural characteristics of various single-element carbons and the origin of the name of fullerene.

This article answers the question "Why can the 'carbon clock' verify the age of ancient organisms", introduces related concepts such as isotopes and the half-life of carbon-14, explains the principle of carbon dating, and also mentions the range of carbon dating, examples of archaeological applications, and the fact that the founder of this method won the Nobel Prize in Chemistry.

This article revolves around the core question of "why Beethoven's hair can be made into brilliant blue diamonds". It introduces the event that Beethoven's hair was made into three blue diamonds by the "Life Treasure" company in 2007 for charity auctions, explains the principle that diamonds and hair both contain carbon elements, which can be extracted into pure carbon through anoxic high-temperature treatment and then processed under high temperature and high pressure to make diamonds. It also mentions that human ashes can also be made into diamonds for memorial purposes, and explains the differences in the composition and formation process of artificial diamonds and natural diamonds, as well as the application fields of artificial diamonds.

This article focuses on the reason why iodine is called the "King of Discoloration", introduces the common characteristics of halogen elements and the basic properties of iodine, explains the discoloration principle of iodine due to its large atomic size and special electron arrangement, and demonstrates iodine's discoloration experiments and related verification methods.

This article focuses on why some table salt needs to be iodized, introducing the importance of iodine to human health, the various hazards of iodine deficiency at different stages, and the preventive role of iodized salt in supplementing iodine. It also explains the multiple uses of iodine in the medical field, and discusses the classification of essential elements in the human body, as well as the functions of trace elements and precautions for their intake.

This article focuses on the effectiveness of fluoride toothpaste in preventing tooth decay. It introduces the characteristics of hydroxyapatite, the main component of teeth, and the causes of tooth decay. It explains the principle of preventing tooth decay by ion exchange between fluoride in fluoride toothpaste and hydroxyapatite in tooth enamel to form acid-resistant fluorapatite, thereby enhancing the tooth's resistance to acid erosion. At the same time, it describes the harm of excessive fluoride intake and the precautions for using fluoride toothpaste.

Fluorine is called the "death element" and stems from the extremely difficult process of separating and preparing simple fluorine. Its chemical properties are active and highly toxic. Many researchers such as David and the Knox brothers have been poisoned and even sacrificed for this. After years of exploration, French chemist Mouisant successfully electrolyzed the preparation of simple fluorine for the first time in 1886 and won the Nobel Prize in Chemistry. He died early due to exposure to poison.

Although rare gases are rare and chemically inactive, they show special abilities in many fields. Liquid helium is used in ultra-low temperature technology, neon gas is used for fog transparent lights, argon gas is used for cosmic radiation detection, krypton gas is used for X-ray shading, xenon gas is used for photodegradation and medical treatment, and mixed gas lasers help high-tech measurement and communication promote development in multiple fields.

This paper focuses on the evolution of the names of rare gases, explaining that rare gases are six gases with low content in the atmosphere. In the early days, they were called "inert gases" due to their stable atomic structure and extremely inactive chemical properties; in 1962, Bartlett synthesized xenon compounds, overthrowing the conclusion that it is completely inert, so it is now renamed rare gases.

This paper combs the evolution of the definition of elements, from the ancient Eastern and Western views to Lavoisier's redefinition of elements in modern times. It details Mendeleev overcoming difficulties to discover the periodic law of elements and predict unknown elements. Later, Mosley revealed the essence of the periodic law and cracked the code of elements.