JEE Main 2018 — Hydrogen Question with Solution
From: JEE Main 2018 (Offline)
Question
Hydrogen peroxide oxidises [Fe(CN)6]4- to [Fe(CN)6]3- in acidic medium but reduces [Fe(CN)6]3- to [Fe(CN)6]4- in alkaline medium. The other products formed are, respectively :
Choose an option
Show full solutionCorrect option: D
Correct answer
DH2O and (H2O + O2)
Step-by-step explanation
In acidic medium, [Fe(CN)6]-3 is oxidise to [Fe(CN)6]-3 by H2O2. So H2O2 will perform reduction reaction.
Reduction reaction of H2O2.
Complete reaction :
[ Fe (CN)6 ]4 + H2O2 + 2H+ 2 [ Fe(CN)6 ] 3 + 2H2O
In alkaline medium, [Fe (CN)6]3 reduce to [ Fe(CN)6 ]4
So H2O2 will oxidize.
Oxidization of H2O2 :
H2
Complete reaction :
[Fe (CN)6 ]3 + H2O2 + 2OH 2 [Fe(CN)6 ] 4 + 2H2O + O2
So, ion acidic medium H2O and in alkaline medium O2 + H2O are produced as by product.
Reduction reaction of H2O2.
Complete reaction :
[ Fe (CN)6 ]4 + H2O2 + 2H+ 2 [ Fe(CN)6 ] 3 + 2H2O
In alkaline medium, [Fe (CN)6]3 reduce to [ Fe(CN)6 ]4
So H2O2 will oxidize.
Oxidization of H2O2 :
H2
Complete reaction :
[Fe (CN)6 ]3 + H2O2 + 2OH 2 [Fe(CN)6 ] 4 + 2H2O + O2
So, ion acidic medium H2O and in alkaline medium O2 + H2O are produced as by product.
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