a)\(Mg+2HCl--.MgCl2+H2\)
X------------------------------------x(mol)
\(2Al+6HCl-->2AlCl3+3H2\)
y--------------------------------------1,5y(mol)
\(Zn+2HCl-->ZnCl2+H2\)
z-------------------------------------z(mol)
\(n_{H2}=\frac{16,352}{22,4}=0,73\left(mol\right)\)
Theo bài ta có hpt
\(\left\{{}\begin{matrix}24x+27y+65z=19,46\\24x-27y=0\\x+1,5y+z=0,73\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=0,27\\y=0,24\\z=0,1\end{matrix}\right.\)
\(\%m_{Mg}=\frac{0,27.24}{19,46}.100\%=33,3\%\)
\(\%m_{Al}=\frac{0,24.27}{19,46}.100\%=33,3\%\)
\(\%m_{Zn}=100-33,3-33,3=33,4\%\)
b)\(n_{HCl}=2n_{H2}=1,46\left(mol\right)\)
\(V_{HCl}=\frac{1,46}{2}=0,73\left(l\right)\)
nH2 = 0.73
gọi nMg=x mol ,nAl=y mol,nZn = z mol
Có hệ sau :24x+27y+65z=19,46
24x=27y
2x+y+2z=0,73.2
=>x = 0.27 mol,
y = 0.24mol
,z = 0.1 mol
mMg = mAl = 6.48 => % Al = %Mg = 33.3%
=> % Zn = 33.4%