a
\(a:2OF\xrightarrow{Dimerisation}\text{F}-\overset{-\,1}{\mathop{\text{O}}}\,-\overset{-\,1}{\mathop{\text{O}}}\,-\text{F}\)

\(\text{b}\,\,:\,\,{{\text{H}}_{4}}{{\text{P}}_{2}}{{\text{O}}_{8}}\xrightarrow{\text{+}\,{{\text{H}}_{2}}\text{O}}\) \(2{{\text{H}}_{3}}\text{P}{{\text{O}}_{4}}+\text{H}-\overset{^{-1}}{\mathop{O}}\,-\overset{^{-1}}{\mathop{\text{O}}}\,-H\)

\(\text{c}\,\,:\,\,\,2\text{Na}\xrightarrow[\Delta ]{excess\,\,{{O}_{2}}}\text{N}{{\text{a}}^{+}}{{\text{O}}^{-}}-{{\text{O}}^{-}}\text{N}{{\text{a}}^{+}}\)