Question

Two reactions and their equilibrium constants are given. A + 2 B − ⇀ ↽ − 2 C K 1 = 2.79 2 C − ⇀ ↽ − D K 2 = 0.186 Calculate the value of the equilibrium constant for the reaction D − ⇀ ↽ − A + 2 B

Answer 1

Answer:

K=1.93

Explanation:

Given reactions are:

A +2B ⇄ 2C  K1=2.79

2C ⇄ D K2=0.186

D⇄ A+ 2B K=?

If we reverse the reaction then the euillibrium constant also become reciprocal of original value:

3rd reaction is a combination of reciprocal of 1st and 2nd reaction

2C⇄A +2B   1/K1;........................1

D ⇄ 2C  1/K2; ..............................2

On adding 1 and 2

D ⇄A +2B    $K=\frac{1}{K1} \times\frac{1}{K2};$

$K=\frac{1}{2.79} \times\frac{1}{0.186};$

K=1.93