Question

The equilibrium constant (KP) is 0.17 at a particular temperature for the reaction: N2O4(g) ⇌ 2NO2(g) Given the following sets of initial conditions, what is the net change that must occur for the reaction to reach equilibrium? Does the reaction shift left to reach equilibrium, does the reaction shift right to reach equilibrium or is the reaction at equilibrium at these initial concentrations so no net change will occur? RIGHT, LEFT, or EQUILIBRIUM

1. PNO2 = 0.252 atm, PN2O4 = 0.144 atm

2. PNO2 = 0.149 atm, PN2O4 = 0.13 atm

3. PNO2 = 0.066 atm, PN2O4 = 0.066 atm

4. PNO2 = 0.167 atm, PN2O4 = 0.054 atm

5. PNO2 = 0.088 atm, PN2O4 = 0.138 atm

Answer 1

1)
Qp = p(NO2)^2 / p(N2O4)
= (0.252)^2 / (0.144)
=0.441

Since Qp >KP, it will move to left

2)
Qp = p(NO2)^2 / p(N2O4)
= (0.149)^2 / (0.13)
=0.17

Since Qp = KP, it is at equilibrium

3)
Qp = p(NO2)^2 / p(N2O4)
= (0.066)^2 / (0.066)
=0.066

Since Qp < KP, it will move to right

4)
Qp = p(NO2)^2 / p(N2O4)
= (0.167)^2 / (0.054)
=0.52

Since Qp >KP, it will move to left

5)
Qp = p(NO2)^2 / p(N2O4)
= (0.088)^2 / (0.138)
=0.056

Since Qp < KP, it will move to right