\(n_{HCl}=0,3.1=0,3\left(mol\right)\\ NaOH+HCl\rightarrow NaCl+H_2O\\ n_{NaOH}=n_{NaCl}=n_{HCl}=0,3\left(mol\right)\\ V_{\text{dd}NaOH}=V=\dfrac{0,3}{2}=0,15\left(l\right)\\ C_{M\text{dd}A}=C_{M\text{dd}NaCl}=\dfrac{0,3}{0,15+0,3}=\dfrac{2}{3}\left(M\right)\)

\(n_{Fe}=\dfrac{11,2}{56}=0,2mol\)

\(Fe+H_2SO_4\rightarrow FeSO_4+H_2\)

0,2     0,2                0,2       0,2

a)\(V_{H_2}=0,2\cdot22,4=4,48l\)

b)\(C_{M_{H_2SO_4}}=\dfrac{0,2}{0,5}=0,4M\)

c)\(C_{M_{FeSO_4}}=\dfrac{0,2}{0,5}=0,4M\)

\(n_{Fe}=\dfrac{11,2}{56}=0,2\left(mol\right)\) 
pthh : \(Fe+H_2SO_4->FeSO_4+H_2\) 
          0,2                                      0,2
=> \(V_{H_2}=0,2.22,4=4,48\left(L\right)\) 
\(m_{H_2SO_4}=\dfrac{0,5}{22,4}.98\approx2,188\left(g\right)\) 
=> mdd=11,2+2,188=13,388(g) 
C%=\(\dfrac{2,188}{13,388}.100\%=16,3\%\)

\(1,n_{Mg}=\dfrac{7,2}{24}=0,3\left(mol\right)\)

PTHH: \(Mg+2HCl\rightarrow MgCl_2+H_2\)

           0,3---->0,6------------------>0,3

\(2,C_{M\left(HCl\right)}=\dfrac{0,6}{0,3}=2M\\ 3,V_{H_2}=0,3.22,4=6,72\left(l\right)\)

\(n_{Fe}=\dfrac{1,12}{56}=0,02\left(mol\right)\)

\(n_{H2SO4}=0,05.1=0,05\left(mol\right)\)

Pt : \(Fe+H_2SO_4\rightarrow FeSO_4+H_2\)

a) Xét tỉ lệ : \(0,02< 0,05\Rightarrow H2SO4dư\)

Theo Pt : \(n_{FeSO4}=n_{H2}=n_{Fe}=0,02\left(mol\right)\)

 \(\Rightarrow V_{H2\left(dktc\right)}=0,02.22,4=0,448\left(l\right)\)

b) \(n_{H2SO4\left(dư\right)}=0,05-0,02=0,03\left(mol\right)\)

\(V_{ddH2SO4\left(dư\right)}=\dfrac{0,03}{1}=0,03\left(l\right)=30\left(ml\right)\)

c) \(C_{MFeSO4}=\dfrac{0,02}{0,05}=0,4\left(M\right)\)

\(C_{MH2SO4\left(dư\right)}=\dfrac{\left(0,05-0,02\right)}{0,05}=0,6\left(M\right)\)

 Chúc bạn học tốt

$n_{Al(NO_3)_3} = n_{Al} = 0,11(mol)$
$\Rightarrow n_{NH_4NO_3} = \dfrac{25,83 - 0,11.213}{80} = 0,03(mol)$
Bảo toàn electron  :$3n_{Al} = 8n_{NH_4NO_3} + 3n_{NO}$

$\Rightarrow n_{NO} = 0,03(mol)$

$V = 0,03.22,4 = 0,672(lít)$
$n_{HNO_3} = 10n_{NH_4NO_3} + 4n_{NO} = 0,42 \Rightarrow x = 0,42 : 2 = 0,21$

$C_{M_{Al(NO_3)_3}} = \dfrac{0,11}{0,21} = 0,52M$
$C_{M_{NH_4NO_3}} = \dfrac{0,03}{0,21} = 0,1428M$

a)

$Fe + H_2SO_4 \to FeSO_4 + H_2$
$n_{H_2SO_4} = n_{H_2} = n_{Fe} = \dfrac{16,8}{56} = 0,3(mol)$

$V = 0,3.22,4 = 6,72(lít)$
$C_{M_{H_2SO_4}} = \dfrac{0,3}{0,25} = 1,2M$

b)

$n_{CuO} = \dfrac{16}{80} = 0,2(mol)$
$CuO + H_2 \xrightarrow{t^o} Cu + H_2O$
$n_{CuO} < n_{H_2}$ nên $H_2$ dư

$n_{Cu} = n_{CuO} = 0,2(mol)$
$m_{Cu} = 0,2.64 = 12,8(gam)$

\(n_{Fe}=\dfrac{m}{M}=\dfrac{16,8}{56}=0,3\left(mol\right)\\ PT:Fe+H_2SO_4\rightarrow FeSO_4+H_2\)

       0,3     0,3                        0,3 (mol)

a) V= n. 22,4 = 0,3 . 22,4 = 6,72(l)

 \(C\%=\dfrac{m_{H_2SO_4}}{m_{dd}}.100\%=\dfrac{0,3.98}{200}.100\%=11,76\%\)

b) PT: \(H_2+CuO\underrightarrow{t^o}Cu+H_2O\)

         0,3                0,3 

=> m_Cu=n.M=0,3.64=19,2(g)

\(n_{Cl_2}=\dfrac{3,36}{22,4}=0,15mol\\ Cl_2+2NaOH\rightarrow NaCl+NaOH+H_2O\\ n_{NaCl}=n_{NaOH}=n_{Cl_2}=0,15mol\\ C_{M_{NaCl}}=\dfrac{0,15}{0,3}=0,5M\\ C_{M_{NaClO}}=\dfrac{0,15}{0,3}=0,5M\)