$\begin{array}{l}1,\\Zn+HNO_3\to Zn(NO_3)_2+NO+H_2O\\\text{Quá trình thăng bằng e:}\\3\times|Zn^0\to Zn^{+2}+2e\\2\times|N^{+5}+3e\to N^{+2}\\PTHH:3Zn+8HNO_3\to 3Zn(NO_3)_2+2NO+4H_2O\\2,\\Al+HNO_3\to Al(NO_3)_3+NO+H_2O\\\text{Quá trình thăng bằng e:}\\1\times|Al^0\to Al^{+3}+3e\\1\times|N^{+5}+3e\to N^{+2}\\PTHH:Al+4HNO3\to Al(NO_3)_3+NO+2H_2O\end{array}$
