a)

Gọi $n_{Zn} = a(mol) ; n_{Al} = b(mol) \Rightarrow 65a + 27b = 11,9(1)$

$Zn + 2HCl \to ZnCl_2 + H_2$
$2Al + 6HCl \to 2AlCl_3 + 3H_2$
Theo PTHH : 

$n_{H_2} = a + 1,5b = \dfrac{8,96}{22,4} = 0,4(2)$

Từ (1)(2) suy ra : a = 0,1; b = 0,2

$m_{Zn} = 0,1.65 = 6,5(gam)$

$m_{Al} = 0,2.27 = 5,4(gam)$

b) $n_{HCl} = 2n_{H_2} = 0,8(mol)$
$C\%_{HCl} = \dfrac{0,8.36,5}{125}.100\% = 23,36\%$

\(n_{H_2}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\\ Fe+2HCl\rightarrow FeCl_2+H_2\\ Zn+2HCl\rightarrow ZnCl_2+H_2\\ Đặt:n_{Fe}=a\left(mol\right);n_{Zn}=b\left(mol\right)\left(a,b>0\right)\\ \Rightarrow\left\{{}\begin{matrix}56a+65b=23,3\\a+b=0,4\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}a=0,3\\b=0,1\end{matrix}\right.\\ \Rightarrow\%m_{Zn}=\dfrac{0,1.65}{23,3}.100\approx27,897\%\\ \Rightarrow\%m_{Fe}\approx72,103\%\)

Fe+2HCl--->FeCl2+H2
    Zn+2HCl-->ZnCl2+H2
Gọi số mol của Fe và Zn lần lượt là x,y mol
=> ta có hpt {56x+65y=23,3
                     {x+y=8,96/22,4
<=>{x=0,3=>mFe=16,8g
      {y=0,1=>mZn=6,5g
nHCl=2nH2=2.8,96/22,4=0,8 mol
=>mHCl=29,2g
%mFe=16,8/23,3.100=72,10300429%
=>%mZn=27,89699571%

Chúc bn học giỏi

Gọi nFe = a (mol); nAl = b (mol)

=> 56a + 27b = 11 (1)

nH2 = 8,96/22,4 = 0,4 (mol)

PTHH: 

Fe + 2HCl -> FeCl2 + H2

a ---> 2a ---> a ---> a

2Al + 6HCl -> 2AlCl3 + 3H2

b ---> 1,5b ---> b ---> b

=> a + 1,5b = 0,4 (2)

Từ (1)(2) => a = 0,1 (mol); b = 0,15 (mol)

mFe = 0,1 . 56 = 5,6 (g)

mAl = 0,2 . 27 = 5,4 (g)

THAM KHẢO :
 

Fe + 2HCl -> FeCl₂ + H₂ (1)

a) 2Al + 6HCl -> 2AlCl₃ + 3H₂ (2)

Gọi khối lượng Fe là x(g) (0<x<11) => n_Fe = x/56 (mol)

Thì m_Al là 11-x(g) => n_Al = (11-x)/27 (mol)

n_H2 = 8,96/22,4 = 0,4 (mol)

Theo PT (1) ta có: n_H2 = n_Fe = x/56 (mol)

Theo PT (2) ta có: n_H2 = 3/2 n_Al = 3/2 . (11-x)/27 = (11-x)/18 (mol)

Theo đề bài, n_H2 thu được là 0,4(mol) nên ta có:

x/56 + (11-x)/18 = 0,4

<=> 18x +56(11-x) = 403,2

<=> x = 5,6 (g)

Do đó: m_Fe = 5,6(g) => n_Fe = 5,6/56 = 0,1 (mol)

m_Al = 11-5,6 = 5,4(g) => n_Al = 5,4/27 = 0,2 (mol)

\(a,n_{H_2}=\dfrac{2,576}{22,4}=0,115\left(mol\right)\\ Đặt:n_{Mg}=a\left(mol\right);n_{Al}=b\left(mol\right)\left(a,b>0\right)\\ Mg+2HCl\rightarrow MgCl_2+H_2\\ 2Al+6HCl\rightarrow2AlCl_3+3H_2\\ \Rightarrow\left\{{}\begin{matrix}95a+133,5b=10,475\\a+1,5b=0,115\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}a=0,04\\b=0,05\end{matrix}\right.\\ \%m_{Mg}=\dfrac{0,04.24}{0,04.24+0,05.27}.100\approx41,558\%\Rightarrow\%m_{Al}\approx58,442\%\\ b,n_{HCl}=2.n_{H_2}=2.0,115=0,23\left(mol\right)\\ \Rightarrow x=C\%_{ddHCl}=\dfrac{0,23.36,5}{100}.100=8,395\%\)

\(n_{HCl}=0,3.1=0,3mol\)

\(2Al+6HCl\rightarrow2AlCl_3+3H_2\)

0,1        0,3                        0,15  ( mol )

\(m_{Al}=0,1.27=2,7g\)

\(\Rightarrow m_{Al}=9,1.2,7=6,4g\)

\(V_{H_2}=0,15.22,4=3,36l\)

nHCl = 0,3 . 1 = 0,3 (mol)

PTHH: 2Al + 6HCl -> 2AlCl3 + 3H2

Mol: 0,1 <--- 0,3 ---> 0,1 ---> 0,15

mAl = 0,1 . 27 = 2,7 (g(

mCu = 9,1 - 2,7 = 6,4 (g)

VH2 = 0,15 . 22,4 = 3,36 (l)

Gọi số mol Al, Fe là a, b

\(m_{Cu}=m_B=6,4\left(g\right)\)

=> \(m_{Al}+m_{Fe}=17,4-6,4=11\left(g\right)\)

=> 27a + 56b = 11

\(n_{H_2}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\)

PTHH: Fe + 2HCl --> FeCl₂ + H₂ 

            b----------------------->b

            2Al + 6HCl --> 2AlCl₃ + 3H₂

             a------------------------>1,5a

=> 1,5a + b = 0,4

=> a = 0,2; b = 0,1

=> \(\left\{{}\begin{matrix}m_{Fe}=0,1.56=5,6\left(g\right)\\m_{Al}=0,2.27=5,4\left(g\right)\end{matrix}\right.\)

\(n_{O_2}=\dfrac{5.6}{22.4}=0.25\left(mol\right)\)

\(n_{H_2}=\dfrac{10.08}{22.4}=0.45\left(mol\right)\)

\(n_{Fe}=a\left(mol\right),n_{Al}=b\left(mol\right)\)

\(3Fe+2O_2\underrightarrow{^{^{t^0}}}Fe_3O_4\)

\(a.......\dfrac{2a}{3}\)

\(4Al+3O_2\underrightarrow{^{^{t^0}}}2Al_2O_3\)

\(b.......\dfrac{3b}{4}\)

\(n_{O_2}=\dfrac{2a}{3}+\dfrac{3b}{4}=0.25\left(mol\right)\left(1\right)\)

\(Fe+2HCl\rightarrow FeCl_2+H_2\)

\(2Al+6HCl\rightarrow2AlCl_3+3H_2\)

\(n_{H_2}=a+1.5b=0.45\left(mol\right)\left(2\right)\)

\(\left(1\right),\left(2\right):a=0.15,b=0.2\)

\(m_{Fe}=0.15\cdot56=8.4\left(g\right)\)

\(m_{Al}=0.2\cdot27=5.4\left(g\right)\)

\(\%m_{Fe}=\dfrac{8.4}{8.4+5.4}\cdot100\%=60.8\%\)

\(\%m_{Al}=100-60.8=39.2\%\)

\(n_{Al}=a\left(mol\right),n_{Fe}=b\left(mol\right)\)

\(m_X=27a+56b=11\left(g\right)\left(1\right)\)

\(n_{H_2}=\dfrac{8.96}{22.4}=0.4\left(mol\right)\)

\(Fe+2HCl\rightarrow FeCl_2+H_2\)

\(2Al+6HCl\rightarrow2AlCl_3+3H_2\)

\(\Rightarrow a+1.5b=0.4\left(2\right)\)

\(\left(1\right),\left(2\right):a=0.1,b=0.2\)

\(n_{HCl}=2n_{H_2}=2\cdot0.4=0.8\left(mol\right)\)

\(m_{dd_{HCl}}=\dfrac{0.8\cdot36.5\cdot100}{14.6}=200\left(g\right)\)

\(\%Fe=\dfrac{0.1\cdot56}{11}\cdot100\%=50.91\%\)

\(\%Al=49.09\%\)