The correct option is A 8.39 g
S+O2→SO2 (I) (Yield = 80%)
SO2+Cl2+2H2O→H2SO4+2HCl (II) (Yield = 60%)
H2SO4+BaCl2→BaSO4+2HCl (III) (Yield = 30%)
In reaction (i),
1 mol of S forms 1 mol of SO2
Again, 8 g sulphur = 832 mol of S = 0.25 mol S
Yield of the reaction is given as 80 %
Actual moles of SO2 formed =0.25×0.80=0.2 mol
In reaction (ii),
1 mol of SO2 forms 1 mol of H2SO4
0.2 mol of SO2 will form 0.2 mol of H2SO4
Yield of the reaction is given as 60 %
Actual amount of H2SO4 formed =0.2×0.60=0.12 mol
In reaction (iii),
1 mol of H2SO4 reacts to form 1 mol of BaSO4
0.12 mol of H2SO4 reacts to form 0.12 mol of BaSO4
Yield of the reaction is given as 30 %
So moles of BaSO4 produced = 0.12×0.3=0.036 mol
Molar mass of BaSO4=137+32+64=233 g
Actual amount of precipitate obtained 0.036×233 g=8.39 g