Có lẽ đề cho dd HCl 1M (1 mol/l) chứ bạn nhỉ?
a, PT: \(2Al+6HCl\rightarrow2AlCl_3+3H_2\)
b, \(n_{Al}=\dfrac{2,7}{27}=0,1\left(mol\right)\)
Theo PT: \(n_{H_2}=\dfrac{3}{2}n_{Al}=0,15\left(mol\right)\Rightarrow V_{H_2}=0,15.22,4=3,36\left(l\right)\)
c, \(n_{HCl}=3n_{Al}=0,3\left(mol\right)\Rightarrow V_{ddHCl}=\dfrac{0,3}{1}=0,3\left(l\right)\)