When atoms participating in a chemical bond exhibit differing electronegativities, the shared electrons are not distributed equally between the nuclei. One atom attracts the electrons more strongly than the other, resulting in an electron density imbalance across the bond. A classic example is observed in water (HO). Oxygen is significantly more electronegative than hydrogen. Consequently, the oxygen atom carries a partial negative charge (-) and each hydrogen atom carries a partial positive charge (+).
This charge separation is fundamental to understanding intermolecular forces, solubility, and chemical reactivity. The resultant attractions between molecules play a vital role in determining the physical properties of substances, such as melting and boiling points. This phenomenon is instrumental in biological systems, influencing protein folding, enzyme-substrate interactions, and the structure of cellular membranes. Its understanding has been crucial in the development of pharmaceuticals, materials science, and the design of novel chemical reactions.
