Em tham khảo nha:
\(\begin{array}{l}
29)\\
Zn + P{b^{2 + }} \to Z{n^{2 + }} + Pb\\
Zn + C{u^{2 + }} \to Z{n^{2 + }} + Cu\\
Zn + 2A{g^ + } \to Z{n^{2 + }} + 2Ag\\
Pb + C{u^{2 + }} \to P{b^{2 + }} + Cu\\
Pb + 2A{g^ + } \to P{b^{2 + }} + 2Ag\\
Cu + 2A{g^ + } \to C{u^{2 + }} + 2Ag\\
30)\\
Mg + 2HCl \to MgC{l_2} + {H_2}\\
Zn + 2HCl \to ZnC{l_2} + {H_2}\\
CuO + {H_2} \xrightarrow{t^0} Cu + {H_2}O\\
{n_{CuO}} = \dfrac{{19,2}}{{64}} = 0,3\,mol\\
{n_{{H_2}}} = {n_{CuO}} = 0,3\,mol\\
{n_{HCl}} = 2{n_{{H_2}}} = 0,6\,mol\\
BTKL:\\
{m_{hh}} + {m_{HCl}} = {m_m} + {m_{{H_2}}}\\
\Rightarrow {m_m} = 15,4 + 0,6 \times 36,5 - 0,3 \times 2 = 36,7g
\end{array}\)
