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Question
Consider the change in the oxidation state of Bromine corresponding to different emf values as shown in the expression below:
\[\ce{BrO^-_4 ->[1.82 V] BrO^-_3 ->[1.5 V] HBrO ->[1.595 V] Br2 ->[1.0652 V] Br^-}\]
Then the species undergoing disproportionation is:
Options
Br2
\[\ce{BrO^-_4}\]
\[\ce{BrO^-_3}\]
HBrO
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Solution
HBrO
Explanation:
(Ecell)A = – 1.82 + 1.5 = – 0.32 V
(Ecell)B = – 1.5 + 1.595 = + 0.095 V
(Ecell)C = 1.595 + 1.0652 = – 0.529 V
∴ The species undergoing disproportionation is HBrO.
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