1)
Phản ứng xảy ra:
\(CuO + 2HCl\xrightarrow{{}}CuC{l_2} + {H_2}O\)
Ta có:
\({n_{CuO}} = \frac{8}{{64 + 16}} = 0,1{\text{ mol}}\)
\( \to {n_{CuC{l_2}}} = {n_{Cu}} = 0,1{\text{ mol}}\)
\( \to {m_{CuC{l_2}}} = 0,1.(64 + 35,5.2) = 13,5{\text{ gam}}\)
\({n_{HCl}} = 2{n_{CuO}} = 0,2{\text{ mol}}\)
\( \to {m_{HCl}} = 0,2.36,5 = 7,3{\text{ gam}}\)
\( \to C{\% _{HCl}} = \frac{{7,3}}{{100}} = 7,3\% \)
2)
Phản ứng xảy ra:
\(MO + {H_2}S{O_4}\xrightarrow{{}}MS{O_4} + {H_2}O\)
Ta có:
\({n_{{H_2}S{O_4}}} = \frac{{19,6}}{{98}} = 0,2{\text{ mol = }}{{\text{n}}_{MO}}\)
\( \to {M_{MO}} = \frac{8}{{0,2}} = 40= {M_M} + 16\)
\( \to {M_M} = 24 \to M:Mg\)
Vậy oxit là \(MgO\)