GC: n
CT: Ions: When atoms have an equal number of protons and electrons, they are neutral and have no electrical charge. However, both man-made and natural forces can act on atoms and result in a gain or loss of electrons.
When a neutral atom has lost an electron (which is negatively charged), the positively charged protons now outnumber the electrons, giving the atom a positive charge. The now positively charged atom is called a positive ion, or a cation.
When a neutral atom has gained an electron (which is negatively charged), the electrons now outnumber the positively charged protons, giving the atom a negative charge. The now negatively charged atom is called a negative ion, or an anion.
There are several forms of energy that can force atoms to give up electrons. These include:
- Chemical energy
- Electrical energy
- Heat energy
- Mechanical energy
- Nuclear energy
- Ionizing radiation.
S: http://teachnuclear.ca/all-things-nuclear/atomic-theory/ions/ (last access: 28 November 2015)
N: 1. Introduced by English physicist and chemist Michael Faraday (suggested by the reverend William Whewell, English polymath) in 1834, coined from Greek ion, neuter present participle of ienai “go,” from PIE root ei- “to go, to walk” (cognates: Greek eimi “I go;” Latin ire “to go,” iter “a way;”). So called because ions move toward the electrode of opposite charge.
Term and definition standardized by ISO in 1997.
2. Ions are electrically charged particles formed when atoms lose or gain electrons. This loss or gain leaves a complete highest energy level, so the electronic structure of an ion is the same as that of a noble gas – such as a helium, neon or argon. If the number of electrons is less than the number of protons, the particle is a positive ion, also called a cation. If the number of electrons is greater than the number of protons, the particle is a negative ion, also called an anion.
The charge on an ion should be:
- The number of charges on an ion formed by a metal is equal to the group number of the metal.
- The number of charges on an ion formed by a non-metal is equal to the group number minus eight.
- Hydrogen forms H+ ions.
3. In the fields of Chemestry and Atomic Physics: An atom, molecule or fragment of a molecule that has acquired an electric charge through the loss or capture of electrons.
In the field of Atmospheric Physics: Any of several types of electrically charged (positive and negative) submicroscopic particles normally found in the atmosphere.
4. Ion exchange is an exchange of ions between two electrolytes or between an electrolyte solution and a complex. In most cases the term is used to denote the processes of purification, separation, and decontamination of aqueous and other ion-containing solutions with solid polymeric or mineralic ‘ion exchangers’.
5. Ionization: the process of splitting up molecules of a substance in positive and negative ions when the substance is dissolved is known as ionization.
S: 1. OED – http://www.etymonline.com/index.php?allowed_in_frame=0&search=ion&searchmode=none (last access: 26 November 2015); TERMIUM PLUS – http://goo.gl/EqWd61 (last access: 28 November 2015). 2. NORTWESTERN.EDU – http://goo.gl/txiVmG (last access: 28 November 2015); BBC – http://goo.gl/qhjYz (last access: 28 November 2015); WHATIS – http://whatis.techtarget.com/definition/ion (last access: 27 November 2015). 3.TERMIUM PLUS – http://goo.gl/ndBP9X (last access: 28 November 2015). 4. AMERSHAM.PHAR – http://labs.mcb.harvard.edu/Gaudet/Resources_Files/GEHealthcare_chromatography/Don‘t%20move/18111421AA.pdf (last access: 27 November 2015); NZI – http://goo.gl/exkWqb (last access: 27 November 2015); LEXBOOK – http://lexbook.net/en/ion-exchange (last access: 27 November 2015); SSWM – http://goo.gl/yIdZPC (last access: 28 November 2015). 5. ELECTRICAL4U – http://goo.gl/Kk1zPB (last access: 28 November 2015); NDT – https://goo.gl/omBrnZ (last access: 28 November 2015).
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CR: adsorption , atom, electron , lepton , linear accelerator, molecule, muon , neutrino , particle, proton , quark , synchrotron, X-rays.
