\({H}_{4} {P}_{2} {O}_{7}\)
\(2 {x}+4(+1)+7(-2)=0\)
\({x}=+5\)
\({H}_{4} {P}_{2} {O}_{5}\)
\(2 {x}+4(+1)+5(-2)=0\)
\({x}=+3\)
\({H}_{4} {P}_{2} {O}_{6}\)
\(2 {x}+4(+1)+6(-2)=0\)
\({x}=+4\)
${CH}_3-\mathrm{CH}_2-\mathrm{CH}_2-\mathrm{Br} \xrightarrow[\Delta]{\mathrm{KOH}_{(a k)}} \mathrm{A} \xrightarrow{\mathrm{HBr}} \mathrm{B} \xrightarrow[\mathrm{KOH}_{(a) i}]{\Delta} \mathrm{C}$