Understanding Voltaic Cells: The Role of Fe3+ in the Anode

  • Thread starter Thread starter Precursor
  • Start date Start date
  • Tags Tags
    Anode Cells
Join the discussion
Registration is free. Start your own thread to ask a follow-up.
1 reply · 5K views
Precursor
Messages
219
Reaction score
0
The problem I have is just a detail I want to clarify about the voltaic cell.

A standard cell is a voltaic cell in which each half-cell contains all entities shown in the half-reaction equation at SATP conditions, with a concentration of 1.0 mol/L for the aqueous solution.

vcrqc4.jpg


Referring to the both the definition and the diagram, what I'm wondering is: why is it necessary to have the Fe 3+ (aq) in the anode solution? It's the product of the oxidation reaction occurring there, so why is it neededthere initially ? This includes not only the particular cell shown above, but all voltaic cells. In general, why is it necessary to have the product of the half-reaction in the anode half? What function does it serve in the cell?
 
Physics news on Phys.org
Generally speaking - there is no need for products to be present initially. They will appear immediately given chance :wink:

However, at STP - by definition - activity of every reagent involved is 1.