The Kp for the reaction is 0.113 at 25 degree C (a) Calculate the Delta G degree

Question

The Kp for the reaction is 0.113 at 25 degree C (a) Calculate the Delta G degree for the reaction. (b) Calculate the Delta G for the reaction when the partial pressures are P_NO_2 = 0.112 atm and P_N_2O_4 = 0.453 atm Using the following information, determine whether or not the reaction below is spontaneous. N_2(g) + 3H_2(g) rightarrow 2 NH_3(g) Delta H degree_rxn = -92.6 kJ/mol Delta S degree_sys = -199 J/K middot mol a) Ammonium nitrate dissolves spontaneously and endothermically in water. What is the sign for Delta S degree, Delta H degree and Delta G degree for the solution process? b) Crystallization of sodium acetate solution occurs spontaneously. What are the signs for Delta S degree, Delta H degree and Delta G degree Reaction: N_2O_4 (g) 2NO_2(g)

Explanation / Answer

Answer (1)

(a)

I think this is what you want to do.
G0=RTlnKp

Here R is the gas constant = 8.31J/K/mol.

T is the absolute temperature = 25+273 = 298 K

K is the equilibrium constant = 0.133

Large values of K result in negative values of G indicating reaction spontaneity.

So G0=RTlnKp

     G0 = ( 8.134 J/K/mol) x (298 K ) x ln ( 0.133 )

      G0 = 4.998 KJ /mol

(b)

Calculate delta G at 298K if the partial pressures of NO2 and N2O4 are 0.112 atm and 0.453 atm respectively.

so it is also G0 = -RTlnKp

Kp = [0.453] / [0.112]^2 = 36.11, therefore ln(36.11) = 3.59

substituting into the equation,

G0 = (-8.314)(298) (3.59 )

G0 = - 8.894 KJ /mol

   

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.