Đáp án:

\(\begin{array}{l}
a)\\
\% Cu = 39\% \\
\% Zn = 31,7\% \\
\% Mg = 29,3\% \\
b)\\
{C_{{M_{{H_2}S{O_4}}}}} = 0,35M
\end{array}\)

Giải thích các bước giải:

\(\begin{array}{l}
Zn + {H_2}S{O_4} \to ZnS{O_4} + {H_2}\\
Mg + {H_2}S{O_4} \to MgS{O_4} + {H_2}\\
{n_{{H_2}}} = \dfrac{{1,568}}{{22,4}} = 0,07mol\\
hh:Zn(a\,mol),Mg(b\,mol)\\
\left\{ \begin{array}{l}
a + b = 0,07\\
65a + 24b = 4,1 - 1,6
\end{array} \right.\\
 \Rightarrow a = 0,02;b = 0,05\\
{m_{Zn}} = 0,02 \times 65 = 1,3g\\
\% Cu = \dfrac{{1,6}}{{4,1}} \times 100\%  = 39\% \\
\% Zn = \dfrac{{1,3}}{{4,1}} \times 100\%  = 31,7\% \\
\% Mg = 100 - 39 - 31,7 = 29,3\% \\
b)\\
{n_{{H_2}S{O_4}}} = {n_{{H_2}}} = 0,07mol\\
{C_{{M_{{H_2}S{O_4}}}}} = \dfrac{{0,07}}{{0,2}} = 0,35M
\end{array}\)

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