Final answer:
In H₂O, each hydrogen atom forms a polar covalent bond with the central oxygen atom by sharing an electron pair. These bonds provide stability to the molecule, with a resultant H-O-H bond angle of approximately 104.5° due to the presence of non-bonding electron pairs on oxygen, creating a distorted tetrahedral shape.
Step-by-step explanation:
The covalent bond in H₂O, or water, consists of two hydrogen (H) atoms each sharing an electron with a central oxygen (O) atom, forming two polar covalent bonds. Each pair of shared electrons constitutes one covalent bond, thereby involving two electrons—one from the oxygen atom and one from each hydrogen atom. This enables the oxygen atom, which ideally requires eight electrons to fill its outer shell, to achieve a stable electronic configuration.
These shared electrons are more strongly attracted to the electronegative oxygen atom, causing it to hold a partial negative charge. Conversely, this attracts the hydrogen atoms to a partial positive charge. This leads to a molecule where the sum of these charges is zero, making the water molecule neutral. While the ideal geometric angle in a tetrahedral arrangement is 109.5°, the presence of non-bonding pairs of electrons results in a distorted tetrahedron, with an H-O-H bond angle of approximately 104.5°.