Final answer:
A water molecule has a bent shape due to the presence of two bonded pairs and two lone pairs of electrons around the central oxygen atom, which is sp³ hybridized.
Step-by-step explanation:
The VSEPR geometry of a water molecule is bent because there are two bonded pairs and two lone pairs around oxygen. In a water molecule, the oxygen atom is sp³ hybridized, where two of the hybrid orbitals are occupied by the lone pairs, and the other two are used for bonding with hydrogen atoms.
This results in the formation of a tetrahedral electron pair geometry, but because lone pairs occupy more space than bonding pairs, the shape of the molecule is distorted into a bent geometry with a bond angle slightly less than the ideal 109.5° of a perfect tetrahedron. Specifically, the observed bond angle in a water molecule is approximately 104.5°.