Al2O3 + 6HCl\(\rightarrow\)2AlCl3 + 3H2O (1)
CuO + 2HCl \(\rightarrow\)CuCl2 + H2O (2)
b;nHCl=0,7.2=1,4(mol)
Đặt nAl2O3=a
nCuO=b
Ta có:
\(\left\{{}\begin{matrix}102a+80b=28,4\\6a+2b=1,4\end{matrix}\right.\)
Giải hệ pt:
a=0,2;b=0,1
mAl2O3=102.0,2=20,4(g)
mCuO=8(g)
c;Theo PTHH 1 ta có:
nAlCl3=2nAl2O3=0,4(mol)
mAlCl3=133,5.0,4=53,4(g)
Theo PTHH 2 ta có:
nCuO=nCuCl2=0,1(mol)
mCuCl2=135.0,1=13,5(g)
d;CM dd AlCl3=\(\dfrac{0,4}{0,7}=0,57M\)
CM dd CuCl2 =\(\dfrac{0,1}{0,7}=0,13M\)
Gọi a, b lần lượt là số mol của Al2O3 và CuO
\(\Rightarrow102a+80b=28,4\left(I\right)\)
\(Al_2O_3\left(a\right)+6HCl\left(6a\right)\rightarrow2AlCl_3\left(2a\right)+3H_2O\)
\(CuO\left(b\right)+2HCl\left(2b\right)\rightarrow CuCl_2\left(b\right)+H_2O\)
\(n_{HCl}=1,4\left(mol\right)\)
Theo PTHH: \(n_{HCl}=6a+2b\left(mol\right)\)
\(\Rightarrow6a+2b=1,4\left(II\right)\)
Từ (I) và (II) \(\Rightarrow\left\{{}\begin{matrix}a=0,2\\b=0,1\end{matrix}\right.\)\(\Rightarrow\left\{{}\begin{matrix}m_{Al_2O_3}=20,4\left(g\right)\\m_{CuO}=8\left(g\right)\end{matrix}\right.\)
Muối sinh ra: \(\left\{{}\begin{matrix}AlCl_3=2a=0,4\left(mol\right)\\CuCl_2=b=0,1\left(mol\right)\end{matrix}\right.\)\(\Rightarrow\left\{{}\begin{matrix}m_{AlCl_3}=53,4\left(g\right)\\m_{CuCl_2}=13,5\left(g\right)\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}C_{M_{AlCl_3}}=\dfrac{0,4}{0,7}=\dfrac{4}{7}\left(M\right)\\C_{M_{CuCl_2}}=\dfrac{0,1}{0,7}=\dfrac{1}{7}\left(M\right)\end{matrix}\right.\)