Sửa đề : 200 ml dung dịch HCl
\(n_{CO_2}=\dfrac{1.12}{22.4}=0.05\left(mol\right)\)
\(n_{HCl}=0.2\left(mol\right)\)
\(MgCO_3+2HCl\rightarrow MgCl_2+CO_2+H_2O\)
\(0.05..............0.1.......0.05.........0.05\)
\(MgO+2HCl\rightarrow MgCl_2+H_2O\)
\(0.05.....0.2-0.1......0.05\)
\(m_{hh}=0.05\cdot84+0.05\cdot40=6.2\left(g\right)\)
\(MgCl_2+2NaOH\rightarrow Mg\left(OH\right)_2+2NaCl\)
\(n_{Mg\left(OH\right)_2}=n_{MgCl_2}=0.1\left(mol\right)\)
\(m_{Mg\left(OH\right)_2}=0.1\cdot58=5.8\left(g\right)\)