Final answer:
Nonpolar molecules have a symmetrical electron distribution with no permanent dipole moment, while polar molecules display asymmetrical electron distribution, often due to different electronegativities of bonded atoms. Polarization is the shift of charges within an object, and a molecule's geometry can also determine its polarity.
Step-by-step explanation:
Definitions of Polar and Nonpolar Molecules
Nonpolar molecules are characterized by a symmetrical distribution of electrons, which results in no permanent dipole moment within the molecule. Examples of such molecules include H-H and F-F, where the atoms share electrons evenly, and CH₄, which has a symmetric tetrahedral geometry ensuring that any internal charges are balanced.
Polar molecules, on the other hand, have an asymmetrical distribution of electrons or an uneven distribution of electronegativity among bonded atoms, leading to a permanent dipole moment. This can occur due to lone pairs of electrons on a central atom or when atoms with different electronegativities form a bond, causing a shift in electron density and resulting in partial positive and negative charges on different parts of the molecule. Water (H₂O) is a typical example of a polar molecule with its bent shape causing an uneven distribution of charge.
Polarization refers to the shifting of positive and negative charges to opposite sides of an atom or molecule. Polarized states are indicative of the separation of positive and negative charges within an object. When considering molecular polarity, it's important to take into account the molecule's geometry, as this can heavily influence whether a molecule is polar or nonpolar.