Equilibrium question

united stars

I'm stuck on a revision question for the following .

Reactant hydrogen + iodine produces 3 hydrogen iodide.

1.9mol Hydrogen and 1.9mol iodine were allowed to reach equilibrium at 710k.

What is equilibrium constant.

I can see the equation is not balanced. I have got the revision answer.
that there is 0.4mol hydrogen and o.4mol iodine

I can not work out how these figures were arrived at. I would appreciate any help.

Reenakjr

Hi United star,


Use law of mass action formula..

aA+bB gives cC+dD---Euation 1

Equilibrium constant (Kc) = [C]c [D]d/[A]a b


The uppercase letters represent chemical species while the lowercase letters represent the corresponding stoichiometric coefficients. The notation [A] represents the molar concentration of species A.

If the species are gases, an entirely analogous expression may be written using partial pressures instead of molar concentrations.

In our case: Kp= PCc PDd/ PAa PBb, P is the partial pressure

1.9 mole/L I2 gas and 1.9 mole/L H2 gas. The two gases are mixed and the above reaction occurs. The variations of the H2, I2, and HI concentrations as a function of time.

The equilibrium constant KC applies to an equilibrium expression written in terms of molar concentrations, and the equilibrium constant KP applies to an equilibrium expression written in terms of partial pressures (with units of atm).

you can convert between KC and KP using the ideal gas law: P = R T C


Good luck......