MgO + SO2 → MgSO3 CaCO3 + SO3 → CaSO4 + CO₂ MgO + 2HC1→ MgCl2 + H2O CaCO3 + 2 HC1→ CaCl2 + H2O + CO₂ SO + Br₂+ H₂O → SO² + 2HBr Br₂(aq) → Br₂(g) SO+Ba²+(aq) → BaSO4(s) Mass of BaSO4 14.5886 g 14.5821 g = 0.0065 1 mol-BaSO 1 met S == Mass of S 0.0065 g BaSO x 233.4 g BaSO 1 mol-BaSO = 8.9 × 10-4 g S 32.07 g S 1 mel S Percentage S = 8.9 × 10-4 g S 1.8939 g sample, x 100% 0.047% = SO+Ba(CIO4)2 → BaSO4(s) + 2C104¯ Volume Ba(CIO4)2 = 4.88 3.40 = 1.48 mL Amount Ba(CIO4)2 = 1.48 mL Ba(CIO)2 × = 3.70 x 10-5 mol Ba(C1O4)2 и 1000 pat 0.0250 mol Ba(CIO4)2 1 L Ba(CIO)2 Next, we calculate the amount of sulfate: Amount SO = 3.70 x 10-5 mol Ba(CIO)2x 1 mol SO- 1 mol Ba(EtO4)2 3.70 x 10-5 mol SO- The mass of sulfur in the original sample comes from the molar masses of sulfur and sulfate ion: Mass of S = 3.70 x 10-5 mol-SO 32.07 g S = 1.19 x 10-3 g S 1 mol-SO The mass of the original sample that was used for the analysis was 2.0023 g, this value is used to calculate the percentage sulfur in the sample. % sulfur 1.19 x 10-3 g S 2.0023 g sample, x 100% 0.0583 % S (a) (b) (c) (d) Figure 4.9 Analysis for sulfate. (a) BaSO, precipitates on addition of excess BaCl2 to the solution containing SO. (b) The solution is filtered to collect the BaSO4. (c) The solid BaSO4 is heated to remove all volatile (easily converted to the gas phase) impurities, then cooled. (d) The BaSO4 is weighed to determine its mass.