Lời giải:\(\begin{array}{l}
+ \,\,{m_Y} = {m_X} + {m_{CO}} - {n_{(CO,\,\,C{O_2})}} = 34,4 + 0,3.28 - 0,3.36 = 32\,\,gam.\\
+ \,\,BTKL\,\,(Y + HN{O_3}) \Rightarrow {n_{{H_2}O}} = \frac{{32 + 1,7.63 - 117,46 - 0,2.16,75.2}}{{18}} = 0,83\, \Rightarrow {n_{N{H_4}^ + }} = \frac{{1,7 - 0,83.2}}{4} = 0,01.\\
+ \,\,\left\{ \begin{array}{l}
{n_{NO}} + {n_{{N_2}O}} = 0,2\\
30{n_{NO}} + 44{n_{{N_2}O}} = 6,7
\end{array} \right. \Rightarrow \left\{ \begin{array}{l}
{n_{NO}} = 0,15\\
{n_{{N_2}O}} = 0,05
\end{array} \right. \Rightarrow \left\{ \begin{array}{l}
{n_{N{O_3}^ - \,\,tao\,\,muoi}} = 1,7 - 0,01 - 0,15 - 0,05.2 = 1,44\\
{m_{(Al,\,\,Fe,\,\,Cu)}} = 117,46 - 1,44.62 - 0,01.18 = 28\,gam.
\end{array} \right.
\end{array}\)
