Đáp án đúng: A
3 : 11.
Đoạn 1: $\displaystyle \text{NaA}l{{O}_{2}}\,+\,HCl\,+\,{{H}_{2}}O\xrightarrow{{}}\,NaCl\,+\,Al{{(OH)}_{3}}\downarrow \,$
${{\text{n}}_{\text{HCl}}}\,\text{=}\,{{\text{n}}_{\text{Al(OH}{{\text{)}}_{\text{3}}}}}\Rightarrow a\text{ }=\text{ }0,06$
Đoạn 2:$\text{Al(OH}{{\text{)}}_{\text{3}}}\,\text{+}\,\text{3HCl}\,\xrightarrow{{}}\,\text{AlC}{{\text{l}}_{\text{3}}}\,\text{+}\,\text{3}{{\text{H}}_{\text{2}}}\text{O}$
${{\text{n}}_{\text{HCl}\,\text{(2)}}}\,\text{=}\,\text{3}{{\text{n}}_{\text{Al(OH}{{\text{)}}_{\text{3}}}\,\,\text{tan}}}\,\Rightarrow \,(b-0,1)\,=\,3.(0,1-0,06)\,\Rightarrow \,\text{b}\,\text{=}\,\text{0}\text{,22}$
