Answer:
∆G = 1.567 kJ/mole
The reaction is nonspontaneous., or will be spontaneous in the reverse direction
Explanation:
<u>Step 1:</u> The balanced equation
H2(g) + I2(g) ⇌ 2HI(g) 2.60 kJ/mol at 25°C.
<u>Step 2:</u> Data given
The initial pressures are:
pH2 = 3.10 atm
pI2 = 1.5 atm
pHI = 1.75 atm
<u>Step 3: </u>Calculate Q
Kp = (pHI)^2 / (pH2)(pI2)
Q has the same form but we substitute the non-equilibrium values given in the problem.
Q = (1.75)² / (3.10*1.5) = 0.659
<u>Step 4:</u> Calculate gibbs free energy
∆G = ∆G˚ + RTlnQ = 2600 J/mole + (8.31 J/mole K)(298 K)(ln 0.659) = 2600 J/mole - 1032.729 J/mole
= 1567.271 J/mole = 1.567 kJ/mole
Interpret ∆G:
∆G > 0 the reaction is nonspontaneous., or will be spontaneous in the reverse direction
∆G < 0 the reaction is spontaneous.
If ∆G = 0 the reaction is essentially at equilibrium.
∆G = 1.567 kJ/mole
The reaction is nonspontaneous., or will be spontaneous in the reverse direction
