Question

"Determine the equilibrium constant, Kgoal, for the reaction 4PCl5(g)⇌P4(s)+10Cl2(g), Kgoal=? by making use of the following information: P4(s)+6Cl2(g)⇌4PCl3(g), K1=2.00×1019 PCl5(g)⇌PCl3(g)+Cl2(g), K2=1.13×10−2"

Answer 1

Answer:

Kgoal = 8.15 X 10⁻²⁸

Explanation:

The goal reaction is

4PCl₅(g)⇌P₄(s)+10Cl₂(g)   Kgoal = ?

The given reactions are

P₄(s)+6Cl₂(g)⇌4PCl₃(g), K₁ = 2.00×10¹⁹

PCl₅(g)⇌PCl₃(g)+Cl₂(g), K₂ = 1.13×10⁻²

We can obtain the goal equation by

i) multiplying the second equation with four

ii) subtracting the equation one from above equation

We know that

i) If we multiply an equation with a number the equilbirium constant increases that times (we have to raise the power of equilibrium constant by that number)

ii) if we subtract two equations the equilibrium constants are divided

Kgoal = (K₂)⁴ / K₁

Kgoal = 8.15 X 10⁻²⁸