Question

Consider the reaction.

A(g)⇌2B(g)

Find the equilibrium partial pressures of A and Bfor each of the different values of Kp. Assume that the initial partial pressure of B in each case is 1.0 atm and that the initial partial pressure of A is 0.0 atm. Make any appropriate simplifying assumptions.

Part A

Kp= 2.4

Part B

Kp= 1.9×10−4

Part C

Kp= 1.8×105

Answer 1

Part A

Kp= 2.4

This is quadratic equation of type with solution

The value 1.425 is discarded as it will lead to negative value for pressure of B.

Hence,

Hence, the equilibrium partial pressure of A atm

The equilibrium partial pressure of B atm

Part B

Kp

This is quadratic equation of type with solution

The value 0.505 is discarded as it will lead to negative value for pressure of B.

Hence,

Hence, the equilibrium partial pressure of A atm

The equilibrium partial pressure of B atm

Part C

Kp

Since Kp is very large, 1.0-2x is approximated to 1.0

Hence, the equilibrium partial pressure of A atm

The equilibrium partial pressure of B atm