Final answer:
The shape and bond angles in a compound are determined by the electron pair repulsion theory, also known as VSEPR theory.
Step-by-step explanation:
The shape and bond angles in a compound are determined by the electron pair repulsion theory, also known as VSEPR theory. According to VSEPR theory, electron pairs in the valence shell of an atom repel each other and try to maximize their separation to minimize repulsion. This leads to the formation of specific molecular shapes and bond angles.
For example, if a molecule contains two bonding pairs and two lone pairs of electrons around a central atom, it will have a bent shape with bond angles of approximately 109.5 degrees. On the other hand, if a molecule contains four bonding pairs and no lone pairs, it will have a tetrahedral shape with bond angles of approximately 109.5 degrees.
The type and number of atoms bonded to the central atom, as well as the presence of lone pairs of electrons, determine the shape and bond angles in a compound.