Question

what is the name of this binary molecular compound? so3 sulfur oxide sulfur trioxide sodium oxide sulfite

Explanation:

Binary molecular compounds naming rules: prefixes are used to indicate the number of each atom. In \(SO_3\), there is one sulfur (\(S\)) atom (prefix "mono - " is often omitted for the first element) and three oxygen (\(O\)) atoms (prefix "tri - "). So it's sulfur trioxide. Sulfur oxide is too general without indicating the number of oxygen atoms. Sodium oxide (\(Na_2O\)) has sodium (\(Na\)) which is not in \(SO_3\). Sulfite (\(SO_3^{2 - }\)) is an ion, not a compound.

Answer:

sulfur trioxide