After passing 6.72 liters of sulfur dioxide gas through the potassium hydroxide solution, 340.5 g of potassium sulfite solution

After passing 6.72 liters of sulfur dioxide gas through the potassium hydroxide solution, 340.5 g of potassium sulfite solution was obtained. Calculate the mass fraction of salt in the resulting solution.

1) Let’s compose the reaction equation:
SO2 + 2KOH = K2SO3 + H2O
2) Calculate the mass and amount of the potassium sulfite substance obtained as a result of the reaction:
n (SO2) = V (SO2) / Vm = 6.72 / 22.4 = 0.3 mol
according to the reaction equation
n (K2SO3) = n (SO2) = 0.3 mol;
3) Determine the mass fraction of potassium sulfite in the solution:
m (K2SO3) = n (K2SO3) ∙ M (K2SO3) = 0.3 ∙ 158 = 47.4 g.
ω (K2SO3) = (m (K2SO3) / m (solution)) ∙ 100% = (47.4 / 340.5) ∙ 100 = 13.92%
Answer: 13.92%