Polarity Sharing Electrons Unevenly

When bonds form between nonmetal atoms, electrons are shared in pairs rather than wholly transferred to form ions. This sharing of electron pairs is called covalent bonding. Different atoms possess varying capacities to attract electrons within a covalent bond, as measured by the electronegativity. So the distribution of shared electrons is not always symmetrical and leads to the idea of polar bonds. There is a continuum of behavior from even sharing (as between like atoms) in covalent bonds, to uneven sharing to form polar covalent bonds, and to complete transfer of electrons from one atom to another to form ionic bonds. 

Consider one of water s two identical covalent bonds. The electrons in this bond are not as evenly shared as they appear in the Lewis structure of water. Within the covalent bond, oxygen attracts the shared electron pair more than hydrogen does. The result is that the electrons are pulled closer to the oxygen atom, causing the electron distribution to be uneven. Covalent bonds with uneven electron distributions are called polar bonds because one side of the bond, the side that is electron deficient, develops a slight positive charge (S ) while the other side of the bond, the side that is electron rich, develops a slight... 

Polar Covalent Bonds Result from an Uneven Sharing of Electrons... 

POLAR COVALENT BONDS RESULT FROM AN UNEVEN SHARING OF ELECTRONS... 

This unequal sharing makes one side of the bond more negative than the other, like poles on a battery. This is shown in Figure 18. Such bonds are called polar bonds. A polar bond is a bond in which electrons are shared unevenly. The bonds between the oxygen atom and hydrogen atoms in the water molecule are another example of polar bonds. 

A polar covalent bond is a bond in which electrons are shared unevenly. 

Uneven sharing of electrons by the atoms in a molecule results in a minute imbalance between negative and positive charges, which causes the molecule to become a miniature magnet or dipole. Polymers are soluble not only when the magnitude of interaiolecular forces is similar to that of potential solvents, but also when their interaiolecular forces contain the same polar contributions. 

Dipole bonds n. Chemical bonds formed when the intramolecular interactions are polar covalent (uneven sharing of electron pair). The strength of the dipole-dipole interaction increases with the polarity of the participating molecules. 

Dipole forces are a result of atoms of different electronegativities. In this case, polar bonds are formed in which electrons are unevenly shared between the bonding atoms. This results in partial negative and partial positive charges on the two bonding atoms. However, the presence of polar bonds within a molecule may or may not make the entire molecule polar, depending on molecular structure. 

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