Answer:
Keq for the new temperature is 26.8
Explanation:
Let's propose the equilibrium:
2IF₅ + I₄F₂ ⇄ 3I₂ + 6F₂
Now we propose the situations:
2IF₅ + I₄F₂ ⇄ 3I₂ + 6F₂
Initial 6 mol 8 mol - -
Initially we added 6 mol and 8 mol of our reactants
React. x x/2 3/2x 3x
By stoichiometry x amount has reacted, so a half of x react to the I₄F₂ and we finally produced 3/2x and 3x in the product side
Eq. (6 - x) (8 - x/2) 3/2x 3x
Notice we have the concentration left for the I₄F₂, so we can find the x value, the amount that has reacted:
8 - x/2 = 6
x = 4, so the concentrations in the equilibrium are:
2 moles of IF₅, 6 moles I₄F₂, 6 moles of I₂ and 12 moles of F₂
As we need molar concentration to determine Keq, we must divide the moles by the volume of the container:
2/10 = [IF₅] → 0.2 M
6/10 = [I₄F₂] → 0.6 M
6/10 = [I₂] → 0.6 M
12/10 = [F₂] → 1.2 M
Let's make, expression for Keq:
Keq = ([I₂]³ . [F₂]⁶) / [IF₅]² . [I₄F₂]
Keq = 0.6³ . 1.2⁶ / 0.2² . 0.6 → 26.8
