Đáp án đúng: C
3,84 gam
$\displaystyle \begin{array}{l}\text{3}{{\text{H}}_{\text{2}}}\text{S}\,\,\text{+}\,\,{{\text{K}}_{\text{2}}}\text{C}{{\text{r}}_{\text{2}}}{{\text{O}}_{\text{7}}}\,\,\text{+ }\,\text{4}{{\text{H}}_{\text{2}}}\text{S}{{\text{O}}_{\text{4}}}\xrightarrow{{}}\text{3S+C}{{\text{r}}_{\text{2}}}{{\text{(S}{{\text{O}}_{\text{4}}}\text{)}}_{\text{3}}}\text{+}{{\text{K}}_{\text{2}}}\text{S}{{\text{O}}_{\text{4}}}\text{+7}{{\text{H}}_{\text{2}}}\text{O}\\\,\,\,\,\,\,\,\,\,\,\,\,\frac{11,76}{294}=0,04\,\,\,\,\,\,\,\xrightarrow{{}}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\text{0,12}\\\Rightarrow {{\text{m}}_{\text{S}}}\text{=3,84}\,\text{gam}\end{array}$
