MCQ
The valency shell of calcium contains
- A$8$ electrons
- B$6$ electrons
- C$4$ electrons
- ✓$2$ electrons
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$Mn{O_2}(s)\, + \,4{H^ + }(aq)\, + \,2{e^ - }\, \to \, M{n^{ + 2}}(aq)\, + \,2{H_2}O(l)\,;$ $E_2^o\, = \,1.21\,\,V$
$MnO_4^{ - 1}(aq)\, + \,4{H^ + }(aq)\, + \,3{e^ - }\, \to \, Mn{O_2}(s)\, + \,3{H_2}O(l)\,;$ $E_3^o\,?$
value of $E_3^o$ will be ............ $\mathrm{V}$