Talk:Ionic bond
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Article Grading: The following comments were left by the quality and importance raters: (edit ยท refresh) Rated "high" as high school/SAT biology content. - tameeria 00:33, 11 March 2007 (UTC) |
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How about a nice caption to say something about the figure - what it represents, how it was made, etc.? -- Marj Tiefert, Wednesday, May 14, 2002
I've done a faily major reformat of this page. If it looks bad to anyone please reformat, or alternativly say what the problem is on this page along with their browser and screen resolution. I'm a bit worried about the equation overlapping the table on the right, which I think it might do with a small enough screen size Theresa knott
- I think the phosphorus anion is fairly unlikely to exist, the third ionisation energy is probably prohibitivly large. In addition to this, since P is a relatively large atom anyway, there will almost undoubtedly be considerable covalency in the bond. Good old NaCl, although for less exotic, is probably a better example. jwasey 16:16, 28 Dec 2004 (UTC)
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[edit] Difference with covalent bonds
Would be great if someone could add a paragraph discussing how exactly they're different from covalent bonds. Tempshill 20:46, 24 Sep 2004 (UTC)
- I think some sort of general bonding page needs to be created which explains either end of the covalent/ionic continuum but emphasises that nothing really exists in these theoretical bonding modes. I don't know how to do this, is it possible? jwasey 16:16, 28 Dec 2004 (UTC)
- Covalent is sharing of electrons and ionic is electrostatic forces of attraction resulting from the non metal having more electrons than protons (so being - ve) and the metal having less electrons than protons (+ve) Tourskin 05:27, 5 February 2007 (UTC)
[edit] Why does it happen?
Since the Lithium and Fluorine atoms are both electrically neutral prior to bonding, what causes an electron to "leave" the Lithium atom for the Fluorine atom in the first place? --RussAbbott 02:27, 17 Nov 2004 (UTC)
- Atoms always "try" to obtain the most stable electron configuration (that of a noble gas). As the Li athom has 1 electron in its last electron shield, it gives up 1 electron and loses its last shield: the next outer shield has 8 electrons, which is a stable configuration. The F has 7 electrons in its last shield: it catches the electron the Li gave up and then has 8 electrons in its last shield: another stable configuration. Maybe this explanation should be in the main article? -- Habbit 17:13, 17 Nov 2004 (UTC)
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- Is it really the case that if there were a free electron floating about in the vicinity of a Fluorine atom, the Fluorine atom would capture it, thereby becoming electrically negative in the process? And is it really the case that a sole Lithium atom expels its sole outershell electron so that it can empty its outermost shell--becoming electrically positive in the process? Neither of these seem likely. Perhaps the two together make more sense. But what is the force that causes it to happen? It isn't an electrical attraction or repulsion (since the two atoms are neutral). In fact, the electron is going in the "wrong" direction with respect to both the Lithium and Fluorine atoms. So it must be something else. What is it? --RussAbbott 23:48, 17 Nov 2004 (UTC)
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doesn't litium have three electrons? I don't think the diagram is right
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It is energetically unfavorable to transfer an electron from Lithium to Fluorine to form separate ions. However, quite a lot of energy is released when the ions pack into the lattice, and this more than compensates for the energy required to form the ions.
I am somewhat suspicious of the statement that no bond is purely ionic. In the compound sodium borohydride, there are Na+ and BH4- ions. There are no lone pairs available on BH4- to share with sodium, so how can there possibly be any covalency?
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- You are forgetting, that covalent bonds aren't just confined to the "sticks between atoms" model. If you think about it using the LCAO model, the borohydride anion has a molecular orbital that is a linear combination of the atomic orbitals; this can then engage in mixing with the remaining electrons floating around the sodium (and the unoccupied shells too). The net energy contribution of this mixing is probably inconsequential next to the "ionic" contribution, however.
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- Dative bonding? Theresa Knott (a tenth stroke) 16:39, 14 August 2005 (UTC)
Well the bond starts off as a covalent bond, with the two atoms sharing lithium's single valence electron. However, their electrongativities are 1.0 for lithium and 4.0 for fluorine. The electronegativity of fluorine is obviously much stronger, so it pulls the electron closer to itself, until it gets to the point that the electron has comletely left lithium and has completed fluorine's octet.24.188.27.7 03:35, 11 December 2005 (UTC)
Ionic Bonding
Ionic bonding reminds me of the mooring lines that get cast into the harbour when the big ship arrives. A sodium atom sails close to a chlorine atom. It takes an interest in it, and then it casts over a mooring electron. The two atoms then haul themselves together. Clearly the bonding has begun before the official explanation for the bond has even come into existence. See 'Gravity Reversal and Atomic Bonding' at http://www.wbabin.net/science/tombe6.pdf Yours sincerely, David Tombe (124.217.36.28 12:22, 8 December 2006 (UTC)).
[edit] Ion pairs?
'ion pair' redirects to this page, but there is no mention of it in the article. From what i understand it is a case when two ions which perhaps were formally attached are still next to each other, but not necessarily bonded. Does this sound about right? Do they influence each other significantly?
- It is virtualy imposible to separate ions enough that they are not bonded to each other any longer. Atempting to do so though the input of considerable energy (in, for example, an electrochemical cell) invariably produces the uncharged elemental atoms. The only instances where ions can exist without some sort of latice or solvent is under extreemly high temperatures (on the level of the corona of the sun) or under vacume conditions where ions can be produced via radiation bombardment. To get back to your quesiton, "Ion Pairs" are always bonded.
[edit] DANGER!!! INACCURATE!!!
Hang on a a day!! Not a minute! This is wrong. The first paragraph states a nonpolar covalent bond is weaker than a covalent polar bond. Okay. But you CAN'T use that to determine if an ionic bond is stronger than a covalent. Because Covalent bonding is very very strong between the actual atoms involved and weak only as an intermolecular force. Ionic bonds are between molecules as in a lattice (intermolecular) and between the actual ions. To prove this, you only need to look at Diamond, Carbon-Carbon bonds, all covalent 100%, with no degree of ionic behavior. Diamond is the hardest material in the world. So I shall remove this very damaging bit at the first paragraph, unless someone with more real scientific knowledge (like a degree or something) rules me wrong. Tourskin.
