For below given chemical reactions: (1) 2Nis) + 02(9) = 2Ni0s) AG; = 471200 + 172T (J/mol) %3D (2) C(s) + 02(9) = CO2(9) AG; = -394100 0.84T (J/mol) %3D (3) C(9) + '/2 O2c9) = CO(g) AG; = -111700' 87.65T (J/mol) %3D a) Calculate the standard Gibbs free energy change at 675, 875 and 1075 K. Plot the AG; - T variation for all three reactions on a single graph. b) Calculate the equilibrium vapor pressure of oxidation reaction (1) at 675, 875 and 1075 K. c) Using the calculated equilibrium vapor pressure values in (b), plot the logPO2 1/T variation and show the stable regions of Ni and NiO on that diagram. d) Calculate the equilibrium constant of oxidation reaction (3) at 675, 875 and 1075 K and from Van't Hoff equation calculate the heat of reaction by using the graphical method.