Final answer:
In a molecule of SF₂, there are 0 double bonds as sulfur forms single bonds with two fluorine atoms to complete its octet.
Step-by-step explanation:
The student asked about the number of double bonds in a molecule of SF₂. The correct answer is a. 0. Sulfur hexafluoride (SF₆) is a type of molecule where the sulfur atom forms six covalent bonds with six fluorine atoms, resulting in an expanded valence shell. However, in the case of SF₂, there are no double bonds because sulfur forms two single bonds with two fluorine atoms, following the octet rule. Sulfur has six valence electrons and needs two more to complete its octet, which it achieves by forming single bonds with two fluorine atoms, each providing one electron.