Write the electronic configuration of Fe²+ and Fe³+. [Fe = 26]. Which out of the two ions is more stable and why?
a) Fe²+: [Ar] 3d⁶, Fe³+: [Ar] 3d⁵
b) Fe²+: [Ar] 3d⁵, Fe³+: [Ar] 3d⁶
c) Fe²+: [Ar] 3d⁴, Fe³+: [Ar] 3d⁷
d) Fe²+: [Ar] 3d⁷, Fe³+: [Ar] 3d⁴