Đáp án:
\(\begin{array}{l}
a)\\
{m_{F{e_3}{O_4}}} = 23,2g\\
b)\\
{V_{{H_2}}} = 4,48l\\
c)\\
{m_{Fe}} = 12,6g
\end{array}\)
Giải thích các bước giải:
\(\begin{array}{l}
a)\\
3Fe + 2{O_2} \to F{e_3}{O_4}\\
{n_{Fe}} = \dfrac{m}{M} = \dfrac{{16,8}}{{56}} = 0,3mol\\
{n_{F{e_3}{O_4}}} = \dfrac{{{n_{Fe}}}}{3} = 0,1mol\\
{m_{F{e_3}{O_4}}} = n \times M = 0,1 \times 232 = 23,2g\\
b)\\
{n_{{O_2}}} = \dfrac{2}{3}{n_{Fe}} = 0,2mol\\
{V_{{H_2}}} = n \times 22,4 = 0,2 \times 22,4 = 4,48l\\
c)\\
F{e_3}{O_4} + 4{H_2} \to 3Fe + 4{H_2}O\\
{n_{{H_2}}} = \dfrac{V}{{22,4}} = \dfrac{{6,72}}{{22,4}} = 0,3mol\\
\dfrac{{0,1}}{1} > \dfrac{{0,3}}{4} \Rightarrow F{e_3}{O_4}\text{ dư}\\
{n_{Fe}} = \dfrac{3}{4}{n_{{H_2}}} = 0,225mol\\
{m_{Fe}} = n \times M = 0,225 \times 56 = 12,6g
\end{array}\)