Chemically bonded hydrogen atom near chemically bonded nitrogen, oxygen, or fluorine atom forms electric dipole {hydrogen bond}|. Nitrogen, oxygen, or fluorine unshared-electron pairs attract hydrogen nuclei. Only nitrogen, oxygen, and fluorine atoms are small enough for unshared-electron pairs to get close enough to hydrogen nucleus.
strength
Electric attraction is one-tenth covalent-bond strength.
time
Hydrogen bonds break and reform in 10^-11 seconds.
forms
Hydrogen bonds can have two configurations. Oxygen atom, hydrogen atom, and atom bonded to hydrogen can be in straight line. This hydrogen-bond type is stronger. Water has many strong-type hydrogen bonds.
At hydrogen, angle of nitrogen, oxygen, or fluorine atom and atom bonded to hydrogen angle can be 109 degrees, as in tetrahedral configuration. This hydrogen-bond type is weaker.
multiplication
Hydrogen bond polarizes atom bonded to hydrogen atom. Polarization aligns other atoms and causes more hydrogen bonding.
Atoms can donate electrons to or accept electrons from other atoms, so one atom becomes positively charged and other atom becomes negatively charged, and opposite ion charges attract {ionic bonding}|. Anions with strong electric forces can gain electrons to fill shell. Cations with strong electric forces can lose electrons to empty shell.
Metal atoms exchange outer electrons to try to fill outer shell {metallic bonding}|. Mercury is liquid, because it has weak metallic bonds.
Two atoms can share two electrons {covalent bond}|, which spend most time between the atomic nuclei and share a bonding orbital. Molecular electron orbitals fill with electrons using same rules as for filling atomic electron orbitals. Bonding orbitals fill before antibonding orbitals. Covalent bonding fills both atoms' outer shells.
antibonding
Shared electrons can spend most time outside the atomic nuclei on line between nuclei, in antibonding orbitals. Outside electrons pull nuclei apart and so oppose covalent chemical bonding. Net bond number equals (bonding electrons - antibonding electrons) / 2.
factor
Atoms with weak electric forces make covalent bonds. Atoms with weak electric forces can gain electrons to complete shell. Atoms with weak electric forces can lose electrons to empty shell.
Two different-electronegativity atoms can bind by sharing electrons, and one atom attracts shared electrons more {polar bond}| {polar covalent bonding}.
Covalent chemical bonds {sigma bond}| {sigma bonding orbital} can overlap atom s orbital and other-atom 1s or 2s orbital, 1p or 2p orbital, or s-p hybrid orbital, with constructive interference and electrons between nuclei. Sigma bonding orbitals are symmetric around line joining the atomic nuclei. Atom s orbital can overlap other-atom 1s or 2s orbital, 1p or 2p orbital, or s-p hybrid orbital {sigma antibonding orbital}, with destructive interference and electrons not between nuclei.
Covalent chemical bonds {pi bond}| {pi bonding orbital} can overlap atom 2p orbitals, so shared electrons are between nuclei but in two regions, one above and one below line between atomic nuclei. Atom 2p orbital can overlap other-atom 2p orbital {pi antibonding orbital}, with destructive interference and electrons not between nuclei.
5-Chemistry-Inorganic-Chemical Bond
Outline of Knowledge Database Home Page
Description of Outline of Knowledge Database
Date Modified: 2022.0225