Question

Calculate ΔG at 25°C for the following reaction:

CO(g) + 2H2(g) → CH3OH(l) ΔG°rxn = -2.9x104 J/mol

when the carbon monoxide has an initial pressure of 5.0 atm and hydrogen gas of 3.0 atm.

Answer 1

∆G is gibbs free energy & ∆G° is gibbs free Energy at standard state Condition.

Kp is equilibrium constant, when partial pressure is taken into consideration. It is written as the ratio of product of partial pressure of product to the product of partial pressure of reactant.

Partial pressure of CH3OH is taken as 1 as it is pure liquid so it will not exert any partial pressure.

Ginen reaction: + २२(१) с он (9) CO (9) 5 atm pa co = Partial pressure of co pk = partial pressure of the 3 atm Chz oh because Kp = P Equilibrium constant (pro) (pth) 2 Cabol is liquid Kp = 5 X (3)2 Kp = 0.0222 T= 25°C=25+273 → T= 298 K 4 OG Xon -2.9x109 J/mol from thermodynamics; AG = AGART lnkp nxn ran Pulting R = Gas constant = 8.314 JIK-mel values - AGE -2.9x10* +8.314x298x en (0.0222) ---P.9x104 9.43 X10 X103 4 ren = -304 30 I 3238tJ imal :: AG = - 3.843X104 Timel CS Scanned with CamScanner