Ta có: \(n_{H_2}=\dfrac{4,48}{22,4}=0,2\left(mol\right)\)
a. PTHH:
\(Mg+2HCl--->MgCl_2+H_2\left(1\right)\)
\(MgO+2HCl--->MgCl_2+H_2O\left(2\right)\)
b. Theo PT(1): \(n_{Mg}=n_{H_2}=0,2\left(mol\right)\)
\(\Rightarrow m_{Mg}=0,2.24=4,8\left(g\right)\)
\(\Rightarrow m_{MgO}=8-4,8=3,2\left(g\right)\)
c. Ta có: \(n_{hh}=0,2+\dfrac{3,2}{40}=0,28\left(mol\right)\)
Theo PT(1,2): \(n_{HCl}=2.n_{hh}=2.0,28=0,56\left(mol\right)\)
\(\Rightarrow m_{HCl}=0,56.36,5=20,44\left(g\right)\)