Question

At 400 K, This Reaction Has Kp 8.2 X 104 What Is Kp At 400 K For The Following Reaction

(A) 8.2 x 104
(B) 2.9 x 102
(C) 6.7x 107
(D) 1.6 x 10-3

Answer 1

The given question is incomplete, here is a complete question.

At 400 K, this Reaction has
`K_p=8.2* 10^(-4)`

`SO_3(g)\rightleftharpoons SO_2(g)+(1)/(2)O_2(g)`

What Is
`K_p` at 400 K for the following reaction?

`2SO_3(g)\rightleftharpoons 2SO_2(g)+O_2(g)`

(A) 8.2 x 10⁻⁴

(B) 2.9 x 10⁻²

(C) 6.7 x 10⁻⁷

(D) 1.6 x 10⁻⁷

Answer : The correct option is, (C)
`6.7* 10^(-7)`

Explanation :

The given chemical equation follows:

`SO_3(g)\rightleftharpoons SO_2(g)+(1)/(2)O_2(g)`

The equilibrium constant for the above equation,
`K_p=8.2* 10^(-4)`.

We need to calculate the equilibrium constant for the following equation of above chemical equation, which is:

`2SO_3(g)\rightleftharpoons 2SO_2(g)+O_2(g)`,
`K_p'`

The equilibrium constant for the doubled reaction will be the square of the initial reaction.

Or, we can say that

If the equation is multiplied by a factor of '2', the equilibrium constant will be the square of the equilibrium constant of initial reaction.

The value of equilibrium constant for the following reaction is:

`K_(p)'=(K_p)^2`

`K_(p)'=(8.2* 10^(-4))^2`

`K_(p)'=6.7* 10^(-7)`

Hence, the value of equilibrium constant for the following reaction is,
`6.7* 10^(-7)`