C-09-Q061mediumsingle_mcqMg(OH)2+2HCl→?\mathrm{Mg(OH)_2 + 2HCl \to ?}Mg(OH)2+2HCl→?aMgCl2+2H2O\mathrm{MgCl_2 + 2H_2O}MgCl2+2H2ObMgCl2+H2\mathrm{MgCl_2 + H_2}MgCl2+H2cMgO+2H2O\mathrm{MgO + 2H_2O}MgO+2H2OdMgCl2+CO2\mathrm{MgCl_2 + CO_2}MgCl2+CO2