a) PTHH: \(2Al+6HCl\rightarrow2AlCl_3+3H_2\)
b) \(n_{Al}=\dfrac{m_{Al}}{M_{Al}}=\dfrac{0,81}{27}=0,03\left(mol\right)\)
\(n_{HCl}=\dfrac{m_{HCl}}{M_{HCl}}=\dfrac{2,19}{36,5}=0,06\left(mol\right)\)
Ta có tỉ lê: \(\dfrac{0,03}{2}>\dfrac{0,06}{6}\Rightarrow Al\) dư
Theo PTHH: \(n_{AlCl_3}=\dfrac{0,06.2}{6}=0,02\left(mol\right)\)
\(\Rightarrow m_{AlCl_3}=0,02.133,5=2,67\left(g\right)\)
Theo PTHH: \(n_{H_2}=\dfrac{0,06.3}{6}=0,03\left(mol\right)\)
\(\Rightarrow m_{H_2}=0,03.2=0,06\left(g\right)\)