Answer
(a) SO
(b) SO$_2$
(c) SO$_3$
(d) S$_2$O
(e) S$_6$O
(f) S$_7$O$_2$
Work Step by Step
(a) SO: Monoxide means one oxygen atom, so this compound has a single oxygen atom bonded to a single sulfur atom.
(b) SO$_2$: Dioxide means two oxygen atoms, so this compound has two oxygen atoms bonded to a single sulfur atom.
(c) SO$_3$: Trioxide means three oxygen atoms, so this compound has three oxygen atoms bonded to a single sulfur atom.
(d) S$_2$O: Disulfur means two sulfur atoms; monoxide means one oxygen atom. This compound contains two sulfur atoms and one oxygen atom.
(e) S$_6$O: Hexasulfur means six sulfur atoms; monoxide means one oxygen atom. This compound contains six sulfur atoms and one oxygen atom.
(f) S$_7$O$_2$: Heptasulfur means seven sulfur atoms; dioxide means two oxygen atoms. This compound contains seven sulfur atoms and two oxygen atoms.
