a) \(2Al+6HCl\rightarrow2AlCl_3+3H_2\uparrow\) (1)
\(CuO+H_2\rightarrow Cu+H_2O\) (2)
b) Ta có : \(n_{Al}=\frac{2,7}{27}=0,1\left(mol\right)\)
Theo PTHH (1): \(n_{H_2}=\frac{3}{2}n_{Al}=0,15\left(mol\right)\)
Theo PTHH (2): \(n_{H_2O}=n_{H_2}=0,15\left(mol\right)\)
\(\Rightarrow m_{H_2O}=0,15\cdot18=2,7\left(g\right)\)
$n_{Al}=2,7/27=0,1mol$
$a.2Al+6HCl\to 2AlCl_3+3H_2(1)$
$H_2+CuO\overset{t^o}\to Cu+H_2O(2)$
$\text{b.Theo pt (1) :}$
$n_{H_2}=3/2.n_{Al}=3/2.0,1=0,15mol$
$\text{Theo pt (2) :}$
$n_{H_2O}=n_{H_2O}=0,15mol$
$=>m_{H_2O}=0,15.18=2,7g$