The equilibrium constant Kc for the following reaction is 3….

The equilibrium constant Kc for the following reaction is 3.18  at 730°C. H2(g) + I2(g)  2 HI(g) Starting with [a] moles of HI in a [b] L reaction vessel, calculate the concentration of HI at equilibrium. round your answer to one decimal place, do not include units.