nAl2O3=10.2:102=0.1(mol)
PTHH:Al2O3+6HCl->2AlCl3+3H2O
theo pthh:nHCl:nAl2O3=6->nHCl=6*0.1=0.6(mol)
mHCl=0.6*36.5=21.9(g)
mdd HCl=21.9*100:14.6=150(g)
theo pthh:nAlCl3:nAl2O3=2->nAlCl3=0.1*2=0.2(mol)
mAlCl3=0.2*133.5=26.7(g)
mdd sau phản ứng:10.2+150=160.2
C%=26.7:160.2*100=16.7%