PTHH:
\(2Ba\left(OH\right)_3+Ba\left(OH\right)_2\rightarrow Ba\left(AlO_2\right)_2+4H_2O\)
\(Al_2\left(SO_4\right)_3+3Ba\left(OH\right)_2\rightarrow3BaSO_4+2Al\left(OH\right)_3\)
Ta có:
\(\left\{{}\begin{matrix}n_{Ba\left(OH\right)2}=0,27\left(mol\right)\\n_{Al2\left(SO4\right)3}=0,08\left(mol\right)\end{matrix}\right.\)
Theo PTHH1 : \(n_{Al\left(OH\right)3}=0,1\left(mol\right)\)
Theo PTHH2: \(\left\{{}\begin{matrix}n_{Ba\left(OH\right)2/du}=0,03\left(mol\right)\\n_{Al\left(OH\right)3}=0,16\left(mol\right)\end{matrix}\right.\)
BTNT Al: \(n_{Al2O3}=0,5.n_{Al\left(OH\right)3}=0,05\left(mol\right)\)
\(\Rightarrow m_{Al2O3}=a=5,1\left(g\right)\)