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Related to cation: anion


(kăt'ī`ən), atom or group of atoms carrying a positive charge. The charge results because there are more protons than electrons in the cation. Cations can be formed from a metal by oxidation (see oxidation and reductionoxidation and reduction,
complementary chemical reactions characterized by the loss or gain, respectively, of one or more electrons by an atom or molecule. Originally the term oxidation
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), from a neutral base (see acids and basesacids and bases,
two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Properties
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) by protonation, or from a polar compound by ionization. Cationic species include Na+, Mg++, and NH4+. The cations of the transition elementstransition elements
or transition metals,
in chemistry, group of elements characterized by the filling of an inner d electron orbital as atomic number increases.
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 have characteristic colors in water solution. Saltssalt,
chemical compound (other than water) formed by a chemical reaction between an acid and a base (see acids and bases). Characteristics and Classification of Salts

The most familiar salt is sodium chloride, the principal component of common table salt.
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 are made up of cations and anionsanion
, atom or group of atoms carrying a negative charge. The charge results because there are more electrons than protons in the anion. Anions can be formed from nonmetals by reduction (see oxidation and reduction) or from neutral acids (see acids and bases) or polar compounds
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. See ionion,
atom or group of atoms having a net electric charge. Positive and Negative Electric Charges

A neutral atom or group of atoms becomes an ion by gaining or losing one or more electrons or protons.
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A positively charged atom or group of atoms, or a radical which moves to the negative pole (cathode) during electrolysis.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


a positively charged ion; an ion that is attracted to the cathode during electrolysis
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005


(1) (IDL On the Net) See IDL.

(2) (ION) An NVIDIA graphics platform typically used in Atom-based netbooks. See Intel Atom.

(3) An ion is an atom with fewer or greater electrons than normal as a result of radiation or chemical reaction. A positive ion, called a "cation" (pronounced "cat-eye-en"), has one or more electrons stripped out, which means it has fewer electrons in its electron shells than it has protons in its nucleus. A negative ion, called an "anion" (pronounced "an-eye-en"), is an atom that has one or more electrons forcibly added.

Cations, Anions, Cathodes and Anodes
Although one might think cations are in cathodes and anions are in anodes, the opposite is true. When the terms were coined, the concept was that positive cations were attracted to the negative cathode, and negative anions were attracted to the positive anode.

Batteries Contain Positive and Negative Ions
In a battery, there are positive ions on one side and negative ions on the other. When a conductor is placed in between to complete the circuit, the electrons flow from the negative ions to the positive side where they join the positive ions. See ion deposition.
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References in periodicals archive ?
As the charge-balancing cation, [Na.sup.+] in the interlayer of Mt tends to hydrate with water molecule, which will result in an increase in basal spacing.
Different cation exchange capacities were obtained by changing the content of ion stabilizers in the slurry fluid based on the existing formula, and the designed addition of the ion stabilizer in the experiment was 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, and 6.0% (Group 1-10).
Effect of dietary cation anion difference on incidence post parturient problems of transition Sahiwal dairy cattle.
Meanwhile, no organic -- and easier to synthesize -- cations that can improve both efficiency and stability have been found so far.
Herein, we report our studies for mixed-cation perovskites using aromatic ammoniums with various linkers between the aromatic ring and the ammonium cation. In particular, a surprising effect of the bulky cations onto the photoluminescence (PL) properties is disclosed.
Pakkanen, "Molecular dynamics study of montmorillonite crystalline swelling: roles of interlayer cation species and water content," Chemical Physics, vol.
where cation concentrations are in [mmol.sub.c] [L.sup.-1] as measured in solution and 0.56 and 0.60 are coefficients relating the dispersive power (inverse of the flocculative power) and flocculative power (Rengasamy and Sumner 1998) of K and Mg, respectively, to Na and Ca, respectively.
In their seminal study of cation effects on soil permeability, Quirk and Schofield (1955) defined the cation concentration low enough to result in a 10% to 15% reduction in the saturated hydraulic conductivity, after leaching with water of known composition for a prescribed time-period, as the threshold concentration (TEC).
Effect of Complexed Alkali Cations on the Dioxygen Affinity and Catalytic Oxidation Abilities of the Cobalt Complexes
It is found that the maximum and equilibrium water absorbency decreases with increasing ionic strength of solution containing multivalent cation as shown in Figs.
Introduction The cation selectivity of macrocyclic ligands such as crown ether and cryptands makes them excellent candidates for analytical applications.