Đáp án đúng: B
Na và K.
$\displaystyle \begin{array}{l}\text{KLK}\,\,\text{R}\,\xrightarrow{\text{HCl}\,\text{+}\,{{\text{H}}_{\text{2}}}\text{O}}\,\text{RCl}\,\text{+}\,\text{ROH}\,\text{+}\frac{\text{1}}{\text{2}}{{\text{H}}_{\text{2}}}\\\Rightarrow \,{{\text{n}}_{\text{HCl}}}\text{+}{{\text{n}}_{{{\text{H}}_{\text{2}}}\text{O}\,}}\text{=}{{\text{n}}_{\text{RCl}}}\,\text{+}\,{{\text{n}}_{\text{O}{{\text{H}}^{\text{-}}}}}\,\text{=}\,\text{2}{{\text{n}}_{{{\text{H}}_{\text{2}}}}}\,\text{=}\,\text{0,25}\\\Rightarrow \,{{\text{M}}_{\text{R}}}\,\text{=}\,\frac{\text{7,35}}{\text{0,25}}\,\text{=}\,\text{29,4}\,\Rightarrow \,\text{Na;}\,\text{K}\end{array}$
