Đáp án:
\(\% {m_{CuO}} = 34,1\% ; \% {m_{F{e_2}{O_3}}} = 65,9\% \)
\({m_{CaC{O_3}}} = 99,45{\text{ gam}}\)
Giải thích các bước giải:
Phản ứng xảy ra:
\(CuO + CO\xrightarrow{{{t^o}}}Cu + C{O_2}\)
\(F{e_2}{O_3} + 3CO\xrightarrow{{{t^o}}}2Fe + 3C{O_2}\)
\(Fe + {H_2}S{O_4}\xrightarrow{{}}FeS{O_4} + {H_2}\)
Kim loại màu đỏ không tan là \(Cu\)
\( \to {n_{Cu}} = \frac{{19,2}}{{64}} = 0,3{\text{ mol = }}{{\text{n}}_{CuO}}\)
\( \to {m_{CuO}} = 0,3.(64 + 16) = 24{\text{ gam}}\)
\( \to {m_{F{e_2}{O_3}}} = 70,4 - 24 = 46,4{\text{ gam}}\)
\( \to \% {m_{CuO}} = \frac{{24}}{{70,4}}.100\% = 34,1\% \to \% {m_{F{e_2}{O_3}}} = 65,9\% \)
\( \to {n_{F{e_2}{O_3}}} = \frac{{46,4}}{{56.2 + 16.3}} = 0,29{\text{ mol}}\)
\( \to {n_{C{O_2}}} = {n_{CuO}} + 3{n_{F{e_2}{O_3}}} = 0,3 + 0,29.3 = 1,17{\text{ mol}}\)
\(Ca{(OH)_2} + C{O_2}\xrightarrow{{}}CaC{O_3} + {H_2}O\)
\( \to {n_{CaC{O_3}{\text{ lt}}}} = {n_{C{O_2}}} = 1,17{\text{ mol}}\)
\( \to {n_{CaC{O_3}}} = 1,17.85\% = 0,9945{\text{ mol}}\)
\( \to {m_{CaC{O_3}}} = 0,9945.100 = 99,45{\text{ gam}}\)