The correct formula for sulfur dioxide is SO₂. This compound consists of one sulfur (S) atom and two oxygen (O) atoms.
In terms of its classification, sulfur dioxide is a molecular compound. This means it is formed by the sharing of electrons between atoms, characteristic of covalent bonding. In contrast, ionic compounds are formed by the transfer of electrons and typically consist of metals and non-metals. Since sulfur dioxide is formed from non-metal elements (sulfur and oxygen) that share electrons, it is categorized as molecular.