Chemistry - Redox Reactions Question with Solution | TestHub

Let equal volumes of R.A in each case be X Meqs

$\begin{array}{ccccc}{\text{MnO}}_4^{-}+8{\text{H}}^{+}+5{\text{e}}^{-}& \to & {\text{Mn}}^{2+}+4{\text{H}}_2\text{O}& \left(\text{Acid}\right)& \left(\text{Z = 5}\right)\\ {\text{MnO}}_4^{-}+2{\text{H}}_2\text{O}+3{\text{e}}^{-}& \to & {\text{MnO}}_2+4{\text{OH}}^{-}& \left(\text{Neutral}\right)& \left(\text{Z = 3}\right)\\ {\text{MnO}}_4^{-}+{\text{e}}^{-}& \to & {\text{MnO}}_4^{2-}& \text{Alkaline}& \left(\text{Z = 1}\right)\end{array}$

$\left(\begin{array}{c}\text{X milli}\text{}\text{eqs}\text{. of}\\ \text{R}\text{.A}\end{array}\right)\text{=}\left(\begin{array}{c}\text{20×1}\\ \text{×5}\end{array}\right)\text{=}\left(\begin{array}{c}\text{33}\text{.3×1}\\ \text{×3}\end{array}\right)\text{=}\left(\begin{array}{c}\text{100×1}\\ \text{×1}\end{array}\right)\text{=100 milli}\text{eqs}$

100 milli eqs. of R.A = 100 milli eqs. of K₂Cr₂O₇

${\text{Cr}}_2{\text{O}}_7^{2-}+14{\text{H}}^{+}+6{\text{e}}^{-}\to 2{\text{Cr}}^{3+}+7{\text{H}}_2\text{O}$

100 milli eqs. of${\text{Cr}}_2{\text{O}}_7^{2-}=6\times 1\times \text{Volume mL,}$

Vol = 16.7 mL