what is polarity

Polarity is a term used in various fields, including chemistry, electricity, magnetism, and biology. In chemistry, polarity refers to the separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment, with a negatively charged end and a positively charged end. The terms "polar" and "nonpolar" are usually applied to covalent bonds, where the polarity is not complete. To determine the polarity of a covalent bond using numerical means, the difference between the electronegativity of the atoms is used. The polarity of a bond arises from the relative electronegativities of the elements. Electronegativity is the power of an atom of an element to attract electrons toward itself when it is part of a compound. A polyatomic molecule will have polar bonds if its atoms are not identical. However, whether or not the molecule as a whole is polar depends on the shape of the molecule. In electricity and magnetism, polarity refers to the direction of the current that determines the polarity of the electromagnetic field. In biology, polarity refers to cell polarity, or the differences in shape, function, and structure of cells.