Final answer:
Oxygen and hydrogen form water through polar covalent bonding and intermolecular hydrogen bonds, due to the higher electronegativity of oxygen which leads to an unequal sharing of electrons.
Step-by-step explanation:
Oxygen and hydrogen connect underwater primarily due to the formation of polar covalent bonds and hydrogen bonds. When oxygen and hydrogen atoms come close together, the atoms share electrons but not equally. Oxygen, having a higher electronegativity, attracts the shared electrons more strongly, leading to a partial negative charge on the oxygen atom and a partial positive charge on the hydrogen atoms.
This difference in electronegativity results in oxygen and hydrogen forming a polar covalent bond. In addition, the slight positive charge of the hydrogen atoms in one water molecule is attracted to the slight negative charge of the oxygen in a neighboring water molecule, forming a special kind of intermolecular attraction known as a hydrogen bond.
This creates a network of interconnected water molecules, which gives water its unique properties, such as a high boiling point and the ability to dissolve many substances.