a) \(n_{H_2}=\dfrac{4,48}{22,4}=0,2\left(mol\right)\)
PTHH:
\(Mg+2HCl->MgCl_2+H_2\) (1)
0,2 0,4 0,2 <-- 0,2 (mol)
\(CuO+2HCl->CuCl_2+H_2O\)
\(n_{Mg}=0,2\left(mol\right)->m_{Mg}=0,2\cdot24=4,8\left(g\right)\)
Ta có \(m_{hh}=m_{Mg}+m_{CuO}\)
<--> \(12,8=4,8+m_{CuO}\)
<--> \(m_{CuO}=8\left(g\right)\)
\(\%m_{Mg}=\dfrac{m_{Mg}}{m_{hh}}\cdot100\%=\dfrac{4,8}{12,8}\cdot100\%=37,5\%\)
\(\%m_{CuO}=\dfrac{m_{CuO}}{m_{hh}}\cdot100\%=\dfrac{8}{12,8}\cdot100\%=62,5\%\)
b) Ta có \(n_{CuO}=\dfrac{8}{80}=0,1\left(mol\right)\)
--> \(n_{HCl\left(2\right)}=0,1\cdot2=0,2\left(mol\right)\)
Tổng mol HCl \(n_{HCl}=0,2+0,4=0,6\left(mol\right)\)
--> \(m_{HCl\left(ct\right)}=0,6\cdot36,5=21,9\left(g\right)\)
--> \(\%C_{HCl}=\dfrac{m_{HCl\left(ct\right)}}{m_{dd\left(HCl\right)}}\cdot100\%=\dfrac{21,9}{200}\cdot100\%=10,95\%\)
Mg+2HCl->MgCl2+H2
0,2----0,4----0,2----0,2
CuO+2HCl->CuCl2+H2
0,1------0,2
n H2=0,2 mol
=>%mMg=\(\dfrac{0,2.24}{12,8}\).100=37,5%
=>%mCuO=62,5%=>n CuO=0,1 mol
->C%=\(\dfrac{0,6.36,5}{200}100=10,95\%\)
