Câu 1:
\(n_{HCl}=0,3\cdot1,5=0,45mol\)
\(n_{khí}=\dfrac{1,12}{22,4}=0,05mol\)
\(CaO+2HCl\rightarrow CaCl_2+H_2O\)
\(MgCO_3+2HCl\rightarrow MgCl_2+H_2O+CO_2\)
0,05 0,1 0,05
\(\Rightarrow2n_{HCl\left(CaO\right)}+2\cdot0,1=0,45\Rightarrow n_{HCl\left(CaO\right)}=0,125mol\)
\(m=\dfrac{0,125}{2}\cdot56+0,05\cdot84=7,7g\)
Câu 2:
\(n_{HCl}=0,4\cdot2=0,8mol\)
\(Al_2O_3+6HCl\rightarrow2AlCl_3+3H_2O\)
x 6x
\(ZnO+2HCl\rightarrow ZnCl_2+H_2O\)
y 2y
\(\Rightarrow\left\{{}\begin{matrix}102x+81y=18,8\\6x+2y=0,8\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=\dfrac{68}{705}\\y=\dfrac{26}{235}\end{matrix}\right.\)
\(\%m_{Al_2O_3}=\dfrac{\dfrac{68}{705}\cdot102}{18,8}\cdot100\%=5,13\%\)
\(\%m_{ZnO}=100\%-5,13\%=94,87\%\)
