\(\begin{array}{l}
1)\\
a)\\
Zn + 2HCl \to ZnC{l_2} + {H_2}\\
nZn = \dfrac{{9,75}}{{65}} = 0,15\,mol\\
nHCl = 2nZn = 0,3\,mol\\
mHCl = 0,3 \times 36,5 = 10,95g\\
b)\\
nZnC{l_2} = nZn = 0,15\,mol\\
mZnC{l_2} = 136 \times 0,15 = 20,4g\\
c)\\
F{e_2}{O_3} + 3{H_2} \to 2Fe + 3{H_2}O\\
n{H_2} = nZn = 0,15\,mol\\
nF{e_2}{O_3} = \dfrac{{0,15}}{3} = 0,05\,mol\\
mF{e_2}{O_3} = 0,05 \times 160 = 8g\\
nFe = \dfrac{{0,15 \times 2}}{3} = 0,1\,mol\\
mFe = 0,1 \times 56 = 5,6g\\
2)\\
a)\\
4Al + 3{O_2} \to 2A{l_2}{O_3}\\
nAl = \dfrac{{10,8}}{{27}} = 0,4\,mol\\
nA{l_2}{O_3} = \dfrac{{0,4}}{2} = 0,2\,mol\\
mA{l_2}{O_3} = 0,2 \times 102 = 20,4g\\
b)\\
n{O_2} = \dfrac{{0,4 \times 3}}{4} = 0,3\,mol\\
V{O_2} = 0,3 \times 22,4 = 6,72l\\
c)\\
2KMn{O_4} \to {K_2}Mn{O_4} + Mn{O_2} + {O_2}\\
nKMn{O_4} = 0,3 \times 2 = 0,6\,mol\\
mKMn{O_4} = 0,6 \times 158 = 94,8g
\end{array}\)
