a) Gọi x là số mol của \(ZnO\), y là số mol của \(Al_2O_3\)
\(PTHH\left(1\right):ZnO+H_2SO_4\rightarrow ZnSO_4+H_2O\)
\(\left(mol\right)\)_______x_________________________x
\(PTHH\left(2\right):Al_2O_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2O\)
\(\left(mol\right)\)________y_________3y_______y___________3y
b) \(m_{ZnO}+m_{Al_2O_3}=m_{hh}\)
\(\Rightarrow81x+102y=28,5\left(1\right)\)
\(n_{H_2SO_4}=\frac{700}{1000}.1=0,7\left(mol\right)\)
\(\Rightarrow x+3y=0,7\left(2\right)\)
\(\xrightarrow[\left(2\right)]{\left(1\right)}\left\{{}\begin{matrix}31x+102y=28,5\\x+3y=0,7\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x=0,1\\y=0,2\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}\%ZnO=\frac{m_{ZnO}}{m_{hh}}.100\%=\frac{0,1.81}{28,5}.100\%\approx28,42\%\\\%Al_2O_3=71,58\%\end{matrix}\right.\)
c)
\(PTHH\left(3\right):ZnO+2HCl\rightarrow ZnCl_2+H_2O\)
\(\left(mol\right)\)_______0,1_____0,2______0,1______0,1
\(PTHH\left(4\right):Al_2O_3+6HCl\rightarrow2AlCl_3+3H_2O\)
\(\left(mol\right)\)_______0,2______1,2______0,4_______0,6
\(\sum m_{HCl}=0,2.36,5+1,2.36,5=51,1\left(g\right)\)
\(C\%_{HCl}=\frac{51,1}{200}.100\%=25,55\%\)
a) PTHH: ZnO+H2SO4-->ZnSO4+H20
x x
Al2O3+3H2SO4-->Al2(SO3)3+3H20
y 3y
b) Gọi x là nZnO, y là nAl2O3
nH2SO4=Cm. V=1. 0,7=0,7 mol
Lập hệ PT: 81X+102Y=28,5
X+3Y=0,7
-->X=0,1 , Y=0,2
%mZnO=0,1.81.100\28,5 =28,42%
-->%mAl2O3=100-28,42=71,56%
c) ZnO+2HCl-->ZnCl2+H2O
0,1 -> 0,2
Al2O3+6HCl-->2AlCl3+3H20
0,2 ->1,2
nHCl=0,2+1,2=1,4 Mol
Ta có:
C%=1,5.36,5.100\200=25,55%
8tk
