<span>Earth has a much greater mass than Pluto does, and therefore has stronger gravity.</span>
Equation is as follow,
Fe₂O₃ + 3 CO → 2 Fe + 3 CO₂
Oxidation:
3 CO → 3 CO₂
Oxidation state of C in CO is +2, and that in CO₂ is +4. So, carbon has lost 2 electrons per mole and 6 electrons per 3 moles hence,
3 CO → 3 CO₂ + 6 e⁻
Reduction:
Fe₂O₃ → 2 Fe
Oxidation state of Fe in Fe₂O₃ is +3 per atom, and that in Fe is 0. So, Iron has gained 3 electrons per atom and 6 electrons per 2 atoms hence,
Fe₂O₃ + 6e⁻ → 2 Fe
Result:
Iron in Fe₂O₃ has been reduced in this reaction and has played a role of oxidizing agent by oxidizing carbon from +2 state to +4 state.
I think the correct answer would be C. The common characteristic that is shareed by the elements found at the center of a period would be that they are the least reactive species. Having lower value of electronegativity, there is less ionization of the atoms which would also contribute to less reactivity.
