Elements questions

Silicon was identified as an element by the French physicist Antoine Lavoisier (1743-1794) in 1787. Stable silicon isotopes are 28Si, 29Si and 30Si. Silicon in nature occurs in the form of silicon dioxide and silicates, never in a free state. It plays an important role in the body - it is necessary along with vitamin C for proper collagen synthesis, conditions faster wound healing, improves the condition of hair, skin and nails, and removes aluminum from the body. It is also a good medium for actively growing tumors (eg leukemia and glioma), so it is forbidden to supplement it.

Bismuth metal has been known since ancient times, although it was often confused with lead and tin, which share some physical properties. The etymology is uncertain, but possibly comes from Arabic bi ismid, meaning having the properties of antimony or the German words weiße Masse or Wismuth ("white mass"), translated in the mid-sixteenth century to New Latin bisemutum.

Iridium was discovered in 1803 among insoluble impurities in natural platinum. Smithson Tennant, the primary discoverer, named iridium for the Greek goddess Iris, personification of the rainbow, because of the striking and diverse colors of its salts. Iridium is one of the rarest elements in Earth's crust, with annual production and consumption of only three tonnes.

Potassium is a chemical element with symbol K (from Neo-Latin kalium).

Protium, deuterium and tritium are hydrogen isotope varieties. Iridium is a chemical element.

Marie Curie was a Polish and naturalized-French physicist and chemist who conducted pioneering research on radioactivity (a term that she coined). Among her many achievements was the discovery of two elements, polonium and radium.

Many of technetium's properties were predicted by Dmitri Mendeleev, who left a gap in his periodic table before the element was discovered. It was finally discovered by Emilio Segrè and Carlo Perrier in 1937 and named after the Greek word τεχνητός, meaning "artificial", since it was the first element to be artificially produced.

A precious metal is a rare, naturally occurring metallic chemical element of high economic value. They are usually ductile and have a high lustre. Historically, precious metals were important as currency, but are now regarded mainly as investment and industrial commodities. Gold, silver, platinum, and palladium each have an ISO 4217 currency code.

A nutrient is a component in foods that is used by an organism to survive and grow. Macronutrients are broken down and converted into the energy needed by an organism's metabolic system to function. Micronutrients provide the necessary cofactors for metabolism to be carried out; they are also used to build and repair tissues and regulate body processes.

Three isotopes of hydrogen occur naturally on the Earth: the most frequent protium (1H), deuterium (2H) and tritium (3H). Other isotopes of hydrogen (4H-7H) were created in laboratories and are highly unstable.