现有\(\rm{200mL}\) \(\rm{MgCl_{2}}\)和\(\rm{AlCl_{3}}\)的混合溶液,其中\(\rm{c(Mg^{2+})=0.2mol⋅L^{-1}}\),\(\rm{c(Cl^{-})=1.3mol⋅L^{-1}}\),要使\(\rm{Mg^{2+}}\)转化为\(\rm{Mg(OH)_{2}}\),并使与\(\rm{Al^{3+}}\)分开,至少需要\(\rm{4mol⋅L^{-1}}\)的\(\rm{NaOH}\)溶液的体积为\(\rm{(}\) \(\rm{)}\)