40 lines
2.7 KiB
Markdown
40 lines
2.7 KiB
Markdown
---
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title: "Electronegativity"
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chunk: 4/4
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source: "https://en.wikipedia.org/wiki/Electronegativity"
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category: "reference"
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tags: "science, encyclopedia"
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date_saved: "2026-05-05T10:52:24.353764+00:00"
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instance: "kb-cron"
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---
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== Group electronegativity ==
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In organic chemistry, electronegativity is associated more with different functional groups than with individual atoms. The terms group electronegativity and substituent electronegativity are used synonymously. However, it is common to distinguish between the inductive effect and the resonance effect, which might be described as σ- and π-electronegativities, respectively. There are several linear free-energy relationships that have been used to quantify these effects, of which the Hammett equation is the best known. Kabachnik Parameters are group electronegativities for use in organophosphorus chemistry.
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== Electropositivity ==
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Electropositivity is a measure of an element's ability to donate electrons, and therefore form positive ions; thus, it is antipode to electronegativity.
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Mainly, this is an attribute of metals, meaning that, in general, the greater the metallic character of an element the greater the electropositivity. Therefore, the alkali metals are the most electropositive of all. This is because they have a single electron in their outer shell and, as this is relatively far from the nucleus of the atom, it is easily lost; in other words, these metals have low ionization energies.
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While electronegativity increases along periods in the periodic table and decreases down groups, electropositivity decreases along periods (from left to right) and increases down groups. This means that elements in the upper right of the periodic table of elements (oxygen, sulfur, chlorine, etc.) will have the greatest electronegativity, and those in the lower left (rubidium, caesium, and francium) the greatest electropositivity.
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== See also ==
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Chemical polarity
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Electron affinity
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Electronegativities of the elements (data page)
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Ionization energy
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Metallic bonding
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Miedema's model
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Orbital hybridization
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Oxidation state
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Periodic table
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== References ==
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== Bibliography ==
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Jolly, William L. (1991). Modern Inorganic Chemistry (2nd ed.). New York: McGraw-Hill. pp. 71–76. ISBN 978-0-07-112651-9.
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Mullay, J. (1987). "Estimation of atomic and group electronegativities". Electronegativity. Structure and Bonding. Vol. 66. pp. 1–25. doi:10.1007/BFb0029834. ISBN 978-3-540-17740-1.
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== External links ==
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Media related to Electronegativity at Wikimedia Commons
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WebElements, lists values of electronegativities by a number of different methods of calculation
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Video explaining electronegativity
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Electronegativity Chart, a summary listing of the electronegativity of each element along with an interactive periodic table |