The gas obtained from the combustion of 6.4 g of sulfur was absorbed in 200 g of concentrated potassium hydroxide solution

The gas obtained from the combustion of 6.4 g of sulfur was absorbed in 200 g of concentrated potassium hydroxide solution. Determine the mass fraction of the formed salt in the solution.

S + O2 → SO2
SO2 + 2KOHconc → K2SO3 + H2O
n (S) = 6.4 / 32 = 0.2 mol – deficient
n (KOH) = 200 / (39 + 17) = 3.57 mol – in excess
m (K2SO3) = 0.2 x (39 x 2 + 32 + 48) = 31.6 g
m solution = 200 + 0.2 x 64 = 212.8 g
ω (K2SO3) = 31.6 / 212.8 x 100% = 14.85%
Answer: the mass fraction of salt (potassium sulfite) formed in the solution is 14.85%.