Question

Consider the change in oxidation state of Bromine corresponding to different emf values as shown in the diagram below : is
Then the species undergoing disproportionation is

• A. $HBrO $
• B. $BrO^{-}_3$
• C. $ Br_2$
• D. $ BrO^{-}_4$

Answer 1

Answer: (A)

$\overset{+1}{HBrO} \longrightarrow B\overset{0}{r _{2}}, E _{ HBrO / Br _{2}}^{0}=1.595\, V$

$\overset{+1}{HBrO} \longrightarrow \overset{+5}{Br}O _{3}^{-}, E _{ BrO _{3}^{-} / HBrO }^{ O }=1.5 \,V$

$E _{\text {cell }}^{\circ}$ for the disproportionation of HBrO,

$E_{\text {cell }}^{\circ}=E_{ HBrO / Br _{2}}^{\circ}-E_{ BrO _{3}^{-} / H B r O}^{\circ}$

$=1.595-1.5$

$=0.095\, V =+ ve$