equilibrium constant?

Question

When 1 mol of gaseous HI is sealed in a 1.00-L flask at 225oC, it decomposes until the
equilibrium amount of I2 present is 0.182 mol:
2HI(g) ⇔ H2(g) + I2(g)
Use these data to calculate Keq for this reaction at 225oC.

Answer 1

2*[HI] <---> [H2] + [I2]

let [I2] = [H2] = x

(c -2x)..<---> ...x........x

(each mole of x reduces initial moles of HI by 2x, since two molecules of HI are needed to produce 1 molecule of H2 or I2)

Keq = [H2]*[I2]/[HI]

Keq = x^2/(c - 2x)

c = 1M, x = [I2] = 0.182

Keq = 0.052

Answer 2

(0.182)^2 = 0.033