Pyrolusite ( X ) KOH , Δ with O 2 Residue ( Y ) O 3 Residue ( Z ) . What is the oxidation number of transition metal in (X), (Y) & (Z) respectively: Fill your answer as sum of digits till you

Question

Pyrolusite ( X ) KOH , Δ with O 2 ​ ​ Residue ( Y ) O 3 ​ ​ Residue ( Z ) . What is the oxidation number of transition metal in (X), (Y) & (Z) respectively: Fill your answer as sum of digits till you get the single digit answer.

TestHub · Accepted Answer

Pyrolusite (X) is MnO₂. The oxidation state of Mn in MnO₂ is +4.

Reaction 1: $2 MnO_{2} + 4 KOH + O_{2} Δ 2 K_{2} MnO_{4} + 2 H_{2} O$

Residue (Y) is K₂MnO₄. The oxidation state of Mn in K₂MnO₄ is +6.

Reaction 2: $2 K_{2} MnO_{4} + O_{3} + H_{2} O \to 2 KMnO_{4} + 2 KOH + O_{2}$

Residue (Z) is KMnO₄. The oxidation state of Mn in KMnO₄ is +7.

The oxidation numbers are +4, +6, +7.

Sum of digits: $4 + 6 + 7 = 17$ .

Single digit sum: $1 + 7 = 8$ .

Chemistry - Redox Reactions Question with Solution | TestHub

Doubts & Discussion