Consider the following reaction:

Question

CaCO3(s)→CaO(s)+CO2(g).
Estimate ΔG∘ for this reaction at each of the following temperatures. (Assume that ΔH∘ and ΔS∘ do not change too much within the given temperature range.)

A) 310K and is it spontaneous
B) 1070K and is it spontaneous
C) 1470K and is it spontaneous

Answer 1

Look up dHo formation and dSo formation.
Then dHo rxn = (n*dHo products) - (dHo reactants)

dSo rxn = (n*dSo products) - (n*dSo reactants)

Then dG = dH - TdS for each temperature
dG = - number is spontaneous
dG = + number is not spontaneous.