chemistry
posted by cody .
At a certain temperature, the Equilibrium constant, Kc, for this reaction is 53.3. At this temperature, 0.500 mol of H2 and 0.500 mol of I2 were placed in a 1.00L container to react. What concentration of HI is present at Equilibrium?
equation: H2 + I2 = 2HI

...........H2 + I2 ==> 2HI
I.........0.50.0.50....0
C.........x....x.....2x
E........0.50x.0.50x..2x
Substitute the E line into Kc expression and solve for x, then 0.50x and 2x. 
Those of you looking at this in the future don't forget the quadratic equation!!!