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Question
Give reasons: E° value for the Mn3+/Mn2+ couple is much more positive than that for Fe3+/Fe2+.
Solution
`E_(Mn^(3+)"/"Mn^(2+))^@` = more positive
`E_(Fe^(3+)"/"Fe^(2+))^@` = less positive
`Mn^(2+) = d^5s^@`
`Mn^(3+) = d^4`
]
Because Mn2+ is more stable than Mn3+. Hence, Mn3+ will have tendency to go in +2 state.
Whereas in case of Fe, Fe3+ is more stable than Fe2+ hence, it have less positive value.
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