When i try to do this problem by simply using a mole ratio, wiley keeps saying it's wrong, what mistake am i making?

Question

If 0.800 mol of liquid CS2 reacts stoichiometrically according to the balanced equation, how many moles of gaseous Cl2 are required?

CS2(l) + 3Cl2(g) → CCl4(l) + S2Cl2(l)

I just used a 1:3 mole ratio

Answer 1

0.800 mol CS2 requires 3 x 0.800 = 2.4 moles Cl2.