Đáp án đúng: A
7,168 lít.
$\displaystyle \begin{array}{l}{{\text{n}}_{\text{BaC}{{\text{O}}_{\text{3}}}}}\,\text{=}\,\frac{\text{15}\text{,76}}{\text{197}}\,\text{=}\,\text{0}\text{,08}\,\text{mol;}\,{{\text{n}}_{\text{Ba(HC}{{\text{O}}_{\text{3}}}{{\text{)}}_{\text{2}}}}}\,\text{=}\,{{\text{n}}_{\text{Ba(OH}{{\text{)}}_{\text{2}}}}}\,\text{-}\,{{\text{n}}_{\text{BaC}{{\text{O}}_{\text{3}}}}}\,\text{=}\,\text{0}\text{,12}\,\text{mol}\\\Rightarrow \,{{\text{n}}_{\text{C}{{\text{O}}_{\text{2}}}}}\,\text{=}\,{{\text{n}}_{\text{BaC}{{\text{O}}_{\text{3}}}}}\,\text{+}\,\text{2}{{\text{n}}_{\text{Ba(HC}{{\text{O}}_{\text{3}}}{{\text{)}}_{\text{2}}}}}\,\text{=}\,\text{0}\text{,32}\,\text{mol}\,\Rightarrow \,\text{V}\,\text{=}\,\text{7}\text{,168}\,\text{lit}\end{array}$
