JAMB - Chemistry (1994 - No. 48)
MnO4(aq) + 8H + 5Fe2+ \(\to\) Mn2+(aq) + 5Fe3+(aq) + H2O. The oxidation number of maganese in the above reaction changed from
+7 to +2
+6 to +2
+5 to +2
+4 to +2
ব্যাখ্যা
\(MnO_{{4}{(aq)}}\) has a charge of \(-1\)
Let the oxidation number of \(Mn\) in \(MnO_{{4}{(aq)}}\) be X
Recall, the oxidation number of \(O_{2}\) is \(-2\)
\(\therefore\) \(X + (-2\times 4) = -1\)
\(X - 8 = -1\)
\(X = +7\)