At a fixed temperature, H2(g), Cl2(g) and HCl(g) exist in eq…

At a fixed temperature, H2(g), Cl2(g) and HCl(g) exist in equilibrium according to the equation: 2HCl(g) ↔ H2(g) + Cl2(g)         Ke = 0.040 In order to have 0.020 mol of Cl2(g) at equilibrium, how many moles of HCl(g) should be initially placed in an empty 1.0 L flask?