lanthanoidi

Lanthanoids, also known as lanthanides, are a group of 15 chemically similar metallic elements. They start with lanthanum (element 57) and end with lutetium (element 71) on the periodic table. These elements are characterized by the filling of the 4f electron shell. The lanthanoids are often found together in nature, typically in mineral ores such as monazite and bastnäsite. Their chemical properties are remarkably similar, which historically made their separation a challenging task. However, subtle differences in their ionic radii and reactivity do exist, which are exploited in various separation techniques. Lanthanoids are considered to be relatively reactive metals. They readily tarnish in air and react with water to produce hydrogen gas. Their compounds are often colored, a property that arises from electronic transitions within the partially filled 4f orbitals. These elements have a wide range of applications, particularly in modern technology. They are crucial components in magnets, lasers, phosphors for displays and lighting, catalysts, and batteries. Their unique optical and magnetic properties make them indispensable in fields like aerospace, electronics, and renewable energy.