$\begin{gathered}
  68g\,\left\{ \begin{gathered}
  CuO \hfill \\
  ZnO \hfill \\ 
\end{gathered}  \right.\, + \,NaO{H_{du}} \to N{a_2}Zn{O_2} + \,{H_2}O\, + \,Cu{O_{khong\,pu}} \hfill \\
  {n_{HCl}} = \frac{{{m_{{\text{dd}}}} \times C\% }}{{M \times 100\% }} = \frac{{8 \times 36.5}}{{36.5 \times 100}} = 0.08\,mol \hfill \\ 
\end{gathered}$

Chất rắn là CuO

$\begin{gathered}
  uO\, + \,2HCl \to CuC{l_2} + {H_2}O \hfill \\
  0.04 \leftarrow 0.08\,\,\,(mol) \hfill \\
   \to \left\{ \begin{gathered}
  {m_{CuO}} = 0.04 \times 80 = 3.2g \hfill \\
  {m_{ZnO}} = 68 - 3.2 = 64.8g \hfill \\ 
\end{gathered}  \right. \to \left\{ \begin{gathered}
  \% CuO = 4.7\%  \hfill \\
  \% ZnO = 100\%  - 4.7\%  = 95.3\%  \hfill \\ 
\end{gathered}  \right. \hfill \\
  {n_{ZnO}} = 64.8/81 = 0.8\,mol \hfill \\
  ZnO\, + \,2NaOH\, \to N{a_2}Zn{O_2} + {H_2}O \hfill \\
  0.8\,mol\,\,\,\xrightarrow{{}}\,\,\,\,\,\,\,0.8\,mol \hfill \\ 
\end{gathered} $

Muối gồm $CuC{l_2}$ và $N{a_2}Zn{O_2}$

$\left\{ \begin{gathered}
  {m_{CuC{l_2}}} = 0.04 \times 135 = 5.4g \hfill \\
  {m_{N{a_2}Zn{O_2}}} = 0.8 \times 143 = 114.4g \hfill \\ 
\end{gathered}  \right.$