Question

In the Mond process for the purification of nickel, carbon monoxide is reacted with heated nickel to produce Ni(CO)4, which is a gas and can therefore be separated from solid impurities:
Ni(s) + 4CO(g) ⇌ Ni(CO)4(g)
Given that the standard free energies of formation of CO(g) and Ni(CO)4(g) are −137.3 and −587.4 kJ/mol, respectively,
calculate the equilibrium constant of the reaction at 86.0°C.
Assume that ΔG o f is temperature-independent.

Answer 1

Answer:

Explanation:

• from ΔG = Summation of ΔGproducts - Summation of ΔGreactants

• Given that the standard free energies of formation of CO(g) = −137.3

• and Ni(CO)4(g)= −587.4 kJ/mol.

• R = gas constant = 8.314

• Temperature = 86.0°C +273 = 359k

• ΔG reaction = −587.4 kJ/mol - (4 x −137.3kJ/mol) =  -38.2kJ/mol

• From the vant hoff Isotherm equation ; ΔG = -RTlnk

• lnk = -38.2kJ/mol / 359 x 8.314

• lnk = -0.0127, k = 0.987