Question

For a given reaction,

$H_2\left(g\right)+I_2\left(g\right)\rightleftharpoons 2HI\left(g\right)$,

$4.5$ moles each of $H_2$ and $I_2$ are heated in a sealed $10L$ vessel. At equilibrium, $3$ mole of $HI$ were found. What is the value of equilibrium constant?

Answer 1

$H_2\left(g\right)+I_2\left(g\right)\rightleftharpoons 2HI\left(g\right)$

Initial moles 4.5 4.5 0

At eq. 4.5 - x 4.5-x 2x

Given:

Moles of HI= 2x = 3

$\therefore$ x = 1.5 moles

The equilibrium constant is :

$K_c=\frac{[HI{]}^2}{\left[H_2\right]\left[I_2\right]}$

$K_c=\frac{(\frac{\text{3 mol}}{\text{10 L}}{)}^2}{\frac{\text{3 mol}}{\text{10 L}}\times \frac{\text{3 mol}}{\text{10 L}}}$

$K_c=1$