\(\text{nH2=13,44/22,4=0,6mol}\)
\(\text{2Al+6HCl=2AlCl3+3H2}\)
=> nAl=0,4mol
=> mAl=10,8g
\(\Rightarrow\text{ mAl2O3=21-10,8=10,2g}\)
2Al+6HCl---->2AlCl3+3H2
n\(_{H2}=\frac{13,44}{22,4}=0,6\left(mol\right)\)
Theo pthh
n\(_{Al}=\frac{2}{3}n_{H2}=0,4\left(mol\right)\)
m\(_{Al}=0,4.27=10,8\left(g\right)\)
m \(_{Al2O3}=21-10,8=10,2\left(g\right)\)