Chemistry question

Question

What is involved in changing Fe²⁺ to Fe³⁺ compared with C₂O₄ ^2-  to 2CO₂ 

Answer 1

For Fe²⁺ to become Fe³⁺, an electron must be lost, i.e. oxidation (option #1)

For C₂O₄^2- to become 2CO₂, there is again electron loss.  Carbon goes from +3 in C₂O₄^2- to +4 in CO₂.  (option #1)