Equilibrium constant and concentrations of HI, H2 and I2

[soulja101]

At 350degress celsius the equilibrium constant is 70. at equlilibrium the concentration if HI is 1.32 mol/L and that of H2 is 0.100 mol/L.
what is the concentration of I2?
would it be 0.32?

 

[chemisttree]

You will need to write out the equilibrium expression for which the constant is 70 before you can continue.