[sw2672]

I want to use Zn or Mn as a reductant in the Nickel-catalyzed reactions.
The yield of reaction might be highly dependent on the state of the reductant.
How do I check the activity of Zn or Mn?
Please help me.

[rolnor]

When you say activated, do you mean like Rieke-type metalls? It would be nice to see what reaction you are working on, I dont understand what you mean by Nickel-catalyzed reaction?

[sw2672]

Zn or Mn metal is usually employed for the reduction of Pd(II) or Ni(II) in the cross coupling reactions. When we used new Zn or Mn metal in this coupling reaction, the yield of product is high, however, when we used old one, the yield decreased. We think their low yields might come from the status of Zn or Mn metal. So we would like to check how amount of Zn or Mn was oxidized.

[phth]

UV/VIS will tell you the oxidation state of the metal.