Here are the essential concepts you must grasp in order to answer the question correctly.
Lanthanides
The elements from cerium (Ce) to lutetium (Lu) are known as lanthanides, a series of 15 metallic elements in the periodic table. They are characterized by their similar properties, including high luster, conductivity, and reactivity. Lanthanides are often used in various applications, such as in strong permanent magnets and phosphors for lighting.
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Metals vs. Nonmetals
Metals are typically characterized by their ability to conduct electricity and heat, malleability, ductility, and a shiny appearance. In contrast, nonmetals are generally poor conductors and are more brittle in solid form. The elements from cerium to lutetium are classified as metals, specifically rare earth metals, due to their metallic properties.
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Electron Configuration
The electron configuration of an element describes the distribution of electrons in its atomic orbitals. For the lanthanides, the 4f subshell is being filled as you move from cerium to lutetium. This filling of the 4f subshell is crucial for understanding the chemical behavior and properties of these elements.
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