Đáp án:
\({m_{Fe}} = 8,4{\text{ gam}}\)
\({C_{M{\text{ HCl}}}} = 1,5M\)
Giải thích các bước giải:
Phản ứng xảy ra:
\(Fe + 2HCl\xrightarrow{{}}FeC{l_2} + {H_2}\)
Ta có:
\({n_{{H_2}}} = \frac{{3,36}}{{22,4}} = 0,15{\text{ mol = }}{{\text{n}}_{Fe}}\)
\( \to {m_{Fe}} = 0,15.56 = 8,4{\text{ gam}}\)
\({n_{HCl}} = 2{n_{Fe}} = 0,15.2 = 0,3{\text{ mol}}\)
\( \to {C_{M{\text{ HCl}}}} = \frac{{0,3}}{{0,2}} = 1,5M\)
\({m_{HCl}} = 0,3.36,5 = 10,95{\text{ gam}}\)
\(\to {m_{dd{\text{ HCl}}}}{\text{ = }}\frac{{10,95}}{{3,65\% }}{\text{ = 300 gam}}\)
BTKL:
\({m_{dd{\text{ muối}}}} = {m_{Fe}} + {m_{dd{\text{ HCl}}}} - {m_{{H_2}}}\)
\( = 8,4 + 300 - 0,15.2 = 308,1{\text{ gam}}\)
\({n_{FeC{l_2}}} = {n_{Fe}} = 0,15{\text{ mol}}\)
\( \to {m_{FeC{l_2}}} = 0,15.(56 + 35,5.2) = 19,05{\text{ gam}}\)
\( \to C{\% _{FeC{l_2}}} = \frac{{19,05}}{{308,1}} = 6,183\% \)