To calculate the enthalpy of formation of SO g , we need to manipulate the given thermochemical equations to obtain the formation reaction of SO g from its elements in their standard states. The formation reaction of SO g is:S s + 3/2 O g SO g First, let's focus on the given equations:1 2SO g + O g 2SO g H = -197 kJ/mol2 2SO g + 2O g 2SO g H = -792 kJ/molWe can notice that equation 1 has the desired product SO and equation 2 has the desired reactants S and O . We can manipulate these equations to obtain the formation reaction of SO g .First, divide equation 1 by 2:1/2 SO g + 1/2 O g SO g H = -98.5 kJ/molNow, we need to obtain S s from SO g . We can do this by subtracting equation 1/2 from equation 2 :2 2SO g + 2O g 2SO g H = -792 kJ/mol- 1/2 SO g + 1/2 O g SO g H = +98.5 kJ/mol--------------------------------------------------------------Result: S s + 3/2 O g SO g H = -693.5 kJ/molSo, the enthalpy of formation of SO g is -693.5 kJ/mol.