Calculate Kp for the reaction at this temperature.

Question

At a given temperature, 1.99 atm of F₂ and 2.88 atm of Br₂ are mixed and allowed to come to equilibrium. The equilibrium pressure of BrF is found to be 1.117 atm. Calculate K_p for the reaction at this temperature.

F₂(g) + Br₂(g) <=> 2 BrF(g). Give answer to 3 decimal places.

Answer 1

F₂(g) + Br₂(g) <==> 2BrF(g)

1.99......2.88.................0........Initial

-x.......-x....................+2x........Change

1.99-x....2.88-x........1.117......Equilibrium

2x = 1.117

x = 0.5585 atm

At equilibrium....

F₂ = 1.99 - 0.559 = 1.431atm

Br₂ = 2.88 - 0.559 = 2.321 atm

BrF = 1.117 atm

Kp = P(BrF)² / P(F₂)P(Br₂) = (1.117)² / (1.431)(2.321)

Kp = 0.376