two atoms with the electronegativity of somthing will likely form a nonpolar covalent bond?
953050
If the difference in the electronegativity between the two elements is less than 1.67, the bond will be covalent.\n\nNote: As to the statement that electronegative atoms don't form covalent bonds, that's nonsense.  ALL atoms are electronegative to some extent.  Just go look up the electronegativity series in any general chem. text.  Or check out this:\nhttp://dbhs.wvusd.k12.ca.us/webdocs/Bonding/Electroneg-Bond-Polarity.html
963808
The ligand will accomodate electrons from the ligands, forming dative bonds.\n\nThe sub-shell also ceases into two groups of orbitals.  One group will be at a higher energy level as compared with the other.  The difference in energy level is acounted by the strength of the ligand, in other words, by its polarising power.  The stronger the ligand, the greater is the energy difference between the two groups of orbitals.
729609
In covalent bonds, elements actually lose and gain electrons to other elements in the compound.  Polar bonds are covalent bonds that don't require hybridization, and Non-Polar bonds do require hybridization.  Ionic bonds occur when elements share an electron but do not lose it.  Therefore, you can tell that NaCl is ionic because Sodium has an extra electron and Chlorine needs one, so Sodium shares it's electron with Chlorine, forming a very strong bond.  Ionic bonds, however are broken by Polar-Bonded liquids such as water, which is why NaCl dissolves.
306495
I'm sorry...my answer to this question, will either sound really smart or really stupid. \n\nMy AP Chemistry class just finished the chapter on bonding. We learned of Ionic bonds, Covalent Bonds, and Hydrogen bonds. \n\nAn ionic bond is a bond between a metal and non-metal and involves the transferring of electrons so that both atoms will become stable but with opposite charges, become attracted to each other, and form a molecule. An example is NaCl or table salt. Na is a metal, Cl is a non-metal.\n\nThe next is covalent bonding between two non-metals or non-metal and metal and involves sharing electrons. An example is O2 - oxygen.\n\nFinally hydrogen bonding is self-explanatory consisting of hydrogen and another element.\n\nBecause of the above, it is chemically impossible for two metals to bond as they will not have enough electrons to stabilize each other in the first place. \n\nI even performed this experiment in class. When a metal is heated it "oxidizes". Its atoms fuse with the oxygen atoms in the air and form the gas. For this reason a metal starts turning brown, as you are simply speeding up the process of rusting.\n\nSo your question is kind of impossible from what I have learned in class. \n\nI'm sorry if I am completely of the point in this answer (if there is something I am not getting and that two metals can actually bond) and I apologize for my ignorance and stupidity in advance. haha
1103437
The most pure covalent bond will be between two identical atoms, since the electronegativity difference between the atoms is zero.
216835
Sp2 non-polar covalent bond
621085
http://www.chemguide.co.uk/atoms/bonding/vdw.html
1064705
I think knowledge of the terms electronegativity and bond energy address your question. \n\nElectronegativity refers to the difference by which two atoms tend to hold onto electrons. You should be able to find a periodic table that shows you the electronegative values of all the atoms. You can compute the electronegativity of a bond between two atoms by subtracting their values from each other (based on Linus Pauling's calculations). For example, Flourine (F) has an electronegativity value of 4 and Na = .9. The electronegative value of an F-Na bond is 3.1 (4 - .9). My old high school textbook (Heath) states that ionic bonds are those having an electronegative difference between 1.7 and 4; polar covalent bonds are between 0.2 and 1.7; covalent (non-polar) bonds are between 0 and 0.2. Thus an F-Na bond by this classification system is an ionic bond.\n\nBut I suppose to answer your question most directly, I would say the evidence that ionic bonds are strong concern something called bond energy. That is, the difference between how much energy is needed to make and break chemical bonds. Generally speaking, the higher the electronegative difference (which translates into more of an ionic bond--see calculation above), the more energy required to break such bonds. \n\nThe bottom line, is that I think this translates into something like the observed boiling points of various substances. Substances that have strong ionic bonds (again, determined by calculation above) I believe have a higher boiling point (because it takes more energy/heat) to break the bonds.
786962
If the molecule has O,N,F,or Cl then most likely it is polar.  Look at the periodic chart and remember that the elements in the upper right are the most electronegative, so they want electrons.  When these elements are in a compound with other atoms such as C and H they will pull electrons closer making a dipole moment.  \n\nThe only real trick is looking at the geometry of the molecule, if there is more than one electronegative atom pulling in opposite directions then the dipole is canceld.  Such as O=C=O which is liniar.\n\nLook at an electronegativity chart you will see what I mean
665955
it must be polar because the structure is tetrahedral with a lone pair at one corner of the tetrahedron and Cl atoms at the  rest three corners. so the individual As-Cl bond moments are not cancelled bcoz of the asymmetry of the molecule and the net polarity cant be zero.
799974
Covalent bond: are those which one or more pairs of electrons are shared by two atoms.\nCovalent chemical bonds involve the sharing of a pair of valence electrons by two atoms, in contrast to the transfer of electrons in ionic bonds. These bonds lead to stable molecules if they share electrons in such a way as to create a noble gas configuration for each atom. \n\nHydrogen gas forms the simplest covalent bond in the diatomic hydrogen molecule. The halogens such as chlorine also exist as diatomic gases by forming covalent bonds. The nitrogen and oxygen which makes up the bulk of the atmosphere also exhibits covalent bonding in forming diatomic molecules. \n\n\n\nIonic Bonds\nIn chemical bonds, atoms can either transfer or share their valence electrons. In the extreme case where one or more atoms lose electrons and other atoms gain them in order to produce a noble gas electron configuration, the bond is called an ionic bond. \n\nTypical of ionic bonds are those in the alkali halides such as sodium chloride, NaCl\n\n\nThe below reference has some diagrams which are helpful as well.
987785
I think you've got it a little backward.  In molecules like water, there is a permanent imbalance of electron distribution in the molecule.  The oxygen atom in water always has a partial negative charge, and the hydrogens are always partially positively charged.  This is so because the electronegativity of oxygen is very large compared to that of hydrogen.  Therefore, when the two elements form covalent bonds in water, the electrons are pulled more strongly toward the oxygen atom, giving it a negative charge.\n\nBecause of this permanent polarity in the molecule, water molecules are dipoles (molecules with two regions of opposite charge).  When two molecules of water interact, they do so through dipole-dipole interactions.  That is, the positive part of one water molecule interacts with the negative part of a different molecule.\n\nInduced dipole interactions occur between non-polar molecules.  Because of the random movement of electrons in a molecule, just by chance the electron distribution will occasionally be lopsided, giving a slight positive charge to one part of the molecule and a slight negative charge to another part.  If this molecule is close to another non-polar molecule, it's partially charged areas will push the electrons away in an adjacent molecule, inducing a dipole in the second molecule.  \n\nSo, dipole-dipole interactions occur between molecules which are already polar, and induced dipole interactions occur between non-polar molecules, or between polar and non-polar molecules.\n\nCheck out a chemistry book for more details.
953238
It is true for individual bonds, but not for molecules.\nThe dipole moment of the molecule will depend on the geometry of the polar covalent bonds. E.g. CF4 has 4 polar bonds but they arranged so that the sum of their dipole moments is zero and the molecule has actually no dipole moment.
82092
just to add to what rb42rdsuns said-\n\nCovalent bonds are formed when atoms "share" electrons so that each nucleus "thinks" that it has, typically, 8 electrons in its valence (outer) shell.  This is typically a lower energy system, which is favorable.  When the two atoms are identical (for example, two hydrogens), the electrons are shared equally  between the atoms.  Sometimes one atom attracts the electrons "better" than the other atom, and this results in a polar bond, in which each of the two atoms has a slight charge.
817547
yes, they always covalently bond with each other under any normal type conditions\n\neven if you were to conveniently have an oxygen cation and anion that you combined, they would lose their ionic nature and bind in a covalent fashion
12669
A covalent bond\nThe other is an Ionic Bond which is when one atom gives an electron to another atom.
20674
The simple answer is probably: covalent bond\n\nI quote: "Covalent bonding is an intramolecular form of chemical bonding characterized by the sharing of one or more pairs of electrons between two species, producing a mutual attraction that holds the resultant molecule together. Atoms tend to share electrons in such a way that their outer electron shells are filled. Such bonds are always stronger than the intermolecular hydrogen bond and similar in strength to or stronger than the ionic bond."