$S _{8( s )}+ a OH ^{-}_{( aq )} \rightarrow b S ^{2-}_{( aq )}+ c S _{2} O _{3}{ }^{2-}{ }_{( aq )}+ d H _{2} O _{(\ell)}$
$'a'$ નું મૂલ્ય ............ છે. (પૂર્ણાક જવાબ)
$C{r_2}O_7^{2 - } + F{e^{2 + }} + {C_2}O_4^{2 - } \to C{r^{3 + }} + F{e^{3 + }} + C{O_2}$ (અસંતુલિત)
$S{O_2}\, + \,\,2{H_2}S\,\,\, \to \,\,3S\,\, + \,\,2{H_2}O$