Đáp án:
7,8g
Giải thích các bước giải:
\(\begin{array}{l}
nS = \dfrac{{3,2}}{{32}} = 0,1\,mol\\
2Al + 3S \to A{l_2}{S_3}\\
\,\,\,\,\,\,\,\,\,\,\,\,\,\,0,1\,\,\,\,\,\,\,\,\,\,\dfrac{1}{{30}}\\
A{l_2}{S_3} + 3{H_2}S{O_4} \to A{l_2}{(S{O_4})_3} + 3{H_2}S\\
\dfrac{1}{{30}}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,0,1\\
nNaOH = 0,2 \times 1 = 0,2\,mol\\
T = \dfrac{{nNaOH}}{{n{H_2}S}} = \dfrac{{0,2}}{{0,1}} = 2
\end{array}\)
T=2=> tạo muối $Na_2S$
\(\begin{array}{l}
2NaOH + {H_2}S \to N{a_2}S + 2{H_2}O\\
0,2\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,0,1\,\,\,\,\,\,\,\,\,\,\,\,\,0,1\\
mN{a_2}S = 0,1 \times 78 = 7,8g
\end{array}\)