Question

Substances A, B, and C can all act as oxidizing agents. In solution, A is green, B is yellow, and C is red. In the reactions in which they participate, they are reduced to A-, B-, and C- ions, all of which are colorless. When a solution of C is mixed with one containing A- ions, the color changes from red to green.
1) Which species is oxidized?
2) Which is reduced?

Answer 1

red (C) goes to colorless (C-) and A- (colorless) goes to green (A).
C + e ==> C-
A- ==> A + e
Oxidation is the loss of electrons.
Reduction is the gain of elec