mH2SO4= 36(g) -> nH2SO4=18/49(mol)
a) PTHH: Fe2O3 + 3 H2SO4 -> Fe2(SO4)3 + 3 H2O
nFe2(SO4)3= nFe2O3= nH2SO4/3= 18/49 : 3=6/49(mol)
=>mFe2O3=6/49 . 160=960/49 (g)
b) mFe2(SO4)3= 400. 6/49=2400/49(g)
mdd(sau)= mFe2O3+ mddH2SO4= 960/49 + 50= 3410/49
=> C%ddFe2(SO4)3= [ (2400/49)/ (3410/49)].100=70,381%
=> C%ddFe2(SO4)3= (48,98/