The presence of excess ions act as an indicator in the redox titration because they turn the solution pink at the end-point. Choices:
Mn^2+
MnO4-
Fe^2+

Determine the reaction and balance the following equations urgent due in the morning

What is the average rate of the reaction between 10 and 20 s?

Element j is 1s 2s 2p 3s . (i) how many unpaired electrons does j have? (ii) is j a good oxidizing agent or a reducing agent? (iii) state reason for the answer.