How much chlorine is required to displace all the iodine contained in 400 g of a solution with a mass fraction of sodium iodide of 15%.

How much chlorine is required to displace all the iodine contained in 400 g of a solution with a mass fraction of sodium iodide of 15%.

Given:
m (solution) = 400g.
w (omega) (NaI) = 15% = 0.15
Find: V (Cl2) -?
Decision:
2NaI + Cl2 = 2NaCl + I2
1.The ratio of the amount of NaI is equal to the amount of Cl2 (according to the reaction equation), which means
n (nu) (NaI) = n (Cl2)
2. Find the mass NaI
m (NaI) = m (solution) * w = 400g * 0.15 = 60g
3.n (NaI) = m / M = 60g / (23 + 127) g / mol = 60g / 150g / mol = 0.4 mol
4. From 1. It follows that n (Cl2) = 0.4 mol
5.V (Cl2) = n * Vm = 0.4 mol * 22.4 l / mol = 8.96 l
Answer: 8.96 liters