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  2. Oxygen - Wikipedia

    en.wikipedia.org/wiki/Oxygen

    Oxygen is the third most abundant chemical element in the universe, after hydrogen and helium. [68] About 0.9% of the Sun's mass is oxygen. [19] Oxygen constitutes 49.2% of the Earth's crust by mass [69] as part of oxide compounds such as silicon dioxide and is the most abundant element by mass in the Earth's crust.

  3. Formal charge - Wikipedia

    en.wikipedia.org/wiki/Formal_charge

    Formal charges in ozone and the nitrate anion. In chemistry, a formal charge (F.C. or q*), in the covalent view of chemical bonding, is the hypothetical charge assigned to an atom in a molecule, assuming that electrons in all chemical bonds are shared equally between atoms, regardless of relative electronegativity.

  4. Elementary charge - Wikipedia

    en.wikipedia.org/wiki/Elementary_charge

    Charge quantization is the principle that the charge of any object is an integer multiple of the elementary charge. Thus, an object's charge can be exactly 0 e, or exactly 1 e, −1 e, 2 e, etc., but not ⁠ 1 / 2 ⁠ e, or −3.8 e, etc. (There may be exceptions to this statement, depending on how "object" is defined; see below.)

  5. Oxidation state - Wikipedia

    en.wikipedia.org/wiki/Oxidation_state

    2 has an overall charge of −1, so each of its two equivalent oxygen atoms is assigned an oxidation state of − ⁠ 1 / 2 ⁠. This ion can be described as a resonance hybrid of two Lewis structures, where each oxygen has an oxidation state of 0 in one structure and −1 in the other. For the cyclopentadienyl anion C 5 H −

  6. Charge number - Wikipedia

    en.wikipedia.org/wiki/Charge_number

    Charge number (denoted z) is a quantized and dimensionless quantity derived from electric charge, with the quantum of electric charge being the elementary charge (e, constant). The charge number equals the electric charge ( q , in coulombs ) divided by the elementary charge: z = q / e .

  7. Valence (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Valence_(chemistry)

    Species with a single charge are univalent (monovalent). For example, the Cs + cation is a univalent or monovalent cation, whereas the Ca 2+ cation is a divalent cation, and the Fe 3+ cation is a trivalent cation. Unlike Cs and Ca, Fe can also exist in other charge states, notably 2+ and 4+, and is thus known as a multivalent (polyvalent) ion. [15]

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    Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!

  9. Mass-to-charge ratio - Wikipedia

    en.wikipedia.org/wiki/Mass-to-charge_ratio

    When charged particles move in electric and magnetic fields the following two laws apply: Lorentz force law: = (+),; Newton's second law of motion: = =; where F is the force applied to the ion, m is the mass of the particle, a is the acceleration, Q is the electric charge, E is the electric field, and v × B is the cross product of the ion's velocity and the magnetic flux density.