Question

Give one oxidising reaction each of kmno4 in neutral, acidic and basic medium

Answer 1

In KMnO4 ,the Mn is +7.

If you put it in an acidic medium, you get this: MnO4¯ +8H+ +5e- → Mn2+ +4H2O As you can see, Mn gives up5 electrons.

In a strongly alkaline solution, you get: MnO4¯ + e- → MnO42- So, it only gives up one of it's electrons. Making it a much weaker oxidizing agent.

In a neutral solution, it gives up3 electrons to form MnO2 and some hydroxide ions.

Answer 2

Equation for reduction of KMnO4

IN ACIDIC MEDIUM

• 8H(+) + MnO4(2-) + 5e(-) --------> Mn(2+) + 4H2O

IN NEUTRAL MEDIUM

• 2H2O + MnO4(-) + 3e(-) ----------> MnO2 + 4OH(-)

IN BASIC MEDIUM

• MnO4(-) + e(-) ----------> MnO4(2-)