Consider the following reaction: 2Ca(s)+O2(g) → 2CaO(s)
ΔH∘rxn= -1269.8 kJ; ΔS∘rxn= -364.6 J/K
Assume that all reactants and products are in their standard states.
A) Calculate the free energy change for the reaction at 35 ∘C.
B) Is the reaction spontaneous?

Rn in the right answer

Answer is: hydrogen is being oxidized.chemical reaction: co₂ + h₂ → co + h₂o.oxidation half reaction: h₂ → 2h⁺ + 2e⁻.reduction half reaction: c⁺⁴ + 2e⁻ → c⁺².oxidation is increase of oxidation number, hydrogen change oxidation number from neutral charge (in molecule of hydrogen) to oxidation number +1 (in water).