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  2. Valence electron - Wikipedia

    en.wikipedia.org/wiki/Valence_electron

    Each hydrogen atom has one valence electron and is univalent. In chemistry and physics, valence electrons are electrons in the outermost shell of an atom, and that can participate in the formation of a chemical bond if the outermost shell is not closed. In a single covalent bond, a shared pair forms with both atoms in the bond each contributing ...

  3. Valence and conduction bands - Wikipedia

    en.wikipedia.org/wiki/Valence_and_conduction_bands

    In solid-state physics, the valence band and conduction band are the bands closest to the Fermi level, and thus determine the electrical conductivity of the solid. In nonmetals, the valence band is the highest range of electron energies in which electrons are normally present at absolute zero temperature, while the conduction band is the lowest range of vacant electronic states.

  4. Electron shell - Wikipedia

    en.wikipedia.org/wiki/Electron_shell

    Electron shell. In chemistry and atomic physics, an electron shell may be thought of as an orbit that electrons follow around an atom 's nucleus. The closest shell to the nucleus is called the "1 shell" (also called the "K shell"), followed by the "2 shell" (or "L shell"), then the "3 shell" (or "M shell"), and so on further and further from ...

  5. Period 3 element - Wikipedia

    en.wikipedia.org/wiki/Period_3_element

    The third period contains eight elements: sodium, magnesium, aluminium, silicon, phosphorus, sulfur, chlorine and argon. The first two, sodium and magnesium, are members of the s-block of the periodic table, while the others are members of the p-block. All of the period 3 elements occur in nature and have at least one stable isotope.

  6. Transition metal - Wikipedia

    en.wikipedia.org/wiki/Transition_metal

    v. t. e. In chemistry, a transition metal (or transition element) is a chemical element in the d-block of the periodic table (groups 3 to 12), though the elements of group 12 (and less often group 3) are sometimes excluded. The lanthanide and actinide elements (the f-block) are called inner transition metals and are sometimes considered to be ...

  7. Electronic band structure - Wikipedia

    en.wikipedia.org/wiki/Electronic_band_structure

    The Pauli exclusion principle limits the number of electrons in a single orbital to two, and the bands are filled beginning with the lowest energy. At the actual diamond crystal cell size denoted by a, two bands are formed, separated by a 5.5 eV band gap. Animation of band formation and how electrons fill them in a metal and an insulator

  8. Group 5 element - Wikipedia

    en.wikipedia.org/wiki/Group_5_element

    primordial element. synthetic element. Group 5 is a group of elements in the periodic table. Group 5 contains vanadium (V), niobium (Nb), tantalum (Ta) and dubnium (Db). [ 1 ] This group lies in the d-block of the periodic table. This group is sometimes called the vanadium group or vanadium family after its lightest member; however, the group ...

  9. Magnesium - Wikipedia

    en.wikipedia.org/wiki/Magnesium

    Magnesium is a chemical element; it has symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic table) it occurs naturally only in combination with other elements and almost always has an oxidation state of +2.