\(n_{Al}=\dfrac{10,8}{27}=0,4\left(mol\right)\)
PT: \(2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)
a, \(n_{Al_2\left(SO_4\right)_3}=\dfrac{1}{2}n_{Al}=0,2\left(mol\right)\)
\(\Rightarrow m_{Al_2\left(SO_4\right)_3}=0,2.342=68,4\left(g\right)\)
b, \(n_{H_2}=\dfrac{3}{2}n_{Al}=0,6\left(mol\right)\)
\(\Rightarrow V_{H_2}=0,6.22,4=13,44\left(l\right)\)