Consider the change in oxidation state of Bromine corredponding to different emf values as shown in the diagram below :
.
The the species undergoing dispropprtionation is .

Options

A. `BrO_(3)^(-)`
B. `BrO_(4)^(-)`
C. `Br_(2)`
D. `HBrO`

Answer

D

Explanation

disproprotionation involves oxidation as well as reaction of the same element
`{:("Species","O.N. of Br"),( B r O_(4)^(-),+7),(BrO_(3)^(-),+5),(HBrO,+1),(Br_(2),0),(Br^(-),-1):}`
`E_(cell)^(@)` corresopinding to compound undergoing disproporitonation reactioin should be positive so that the reaction is spontaneous `(DeltaG^(@)=-2FE^(@))`
`overset(+5)(BrO_(3))underset(1.5V)overset("oxidation")larroberset(+1)(HBrO)underset(1.59V)overset("reduction")tooverset(0)(Br_(2))`
`E_(cell)^(@)=E_(R)^(@)-E_(L)^(@)`
`=(1.595V)-(1.5V)`
`=0.095V`
Since `E_(cell)^(@)` is +ve, `DeltaG^(@)` will be negative i.e., HBrO will undergo disproportionation reaction.