a, PT: \(Zn+2HCl\rightarrow ZnCl_2+H_2\)

b, Ta có: \(n_{Zn}=\dfrac{6,5}{65}=0,1\left(mol\right)\)

Theo PT: \(n_{H_2}=n_{Zn}=0,1\left(mol\right)\Rightarrow V_{H_2}=0,1.22,4=2,24\left(l\right)\)

c, PT: \(Fe_2O_3+3H_2\underrightarrow{t^o}2Fe+3H_2O\)

Theo PT: \(n_{Fe}=\dfrac{2}{3}n_{H_2}=\dfrac{1}{15}\left(mol\right)\Rightarrow m_{Fe}=\dfrac{1}{15}.56=\dfrac{56}{15}\left(g\right)\)

a: \(n_{Fe}=\dfrac{11.2}{56}=0.2\left(mol\right)\)

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

0,2      0,4        0,2         0,2

\(V_{H_2}=0,2\cdot22,4=4,48\left(lít\right)\)

b: \(\dfrac{n_{HCl}}{V_{HCl}}=2\)

=>\(\dfrac{0.4}{V_{HCl}}=2\)

=>\(V_{HCl}=\dfrac{0.4}{2}=0.2\left(lít\right)\)

c: \(C_M=\dfrac{n}{V}=\dfrac{0.2}{0.2}=1\)

Bài 3:

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

a, PTHH: Fe₃O₄ + 4H₂ --t^o--> 3Fe + 4H₂O

                0,1<------0,4

              Zn + 2HCl ---> ZnCl₂ + H₂

             0,4<-------------------------0,4

b, m_Fe3O4 = 0,1.232 = 23,2 (g)

c, m_Zn = 0,4.65 = 26 (g)

Bài 4:

\(n_{Zn}=\dfrac{6,5}{65}=0,1\left(mol\right)\)

a, PTHH: Zn + 2HCl ---> ZnCl₂ + H₂

              0,1---->0,2---------------->0,1

b, V_H2 = 0,1.22,4 = 2,24 (l)

c, \(C_{M\left(HCl\right)}=\dfrac{0,2}{0,2}=1M\)

a) Fe + 2HCl --> FeCl₂ + H₂

b) \(n_{Fe}=\dfrac{8,4}{56}=0,15\left(mol\right)\)

PTHH: Fe + 2HCl --> FeCl₂ + H₂

         0,15-->0,3---->0,15-->0,15

=> V_H2 = 0,15.22,4 = 3,36 (l)

c) \(m_{dd.HCl}=\dfrac{0,3.36,5}{7,3\%}=150\left(g\right)\)

\(n_{Fe}=\dfrac{8,4}{56}=0,15\left(mol\right)\\ pthh:Fe+2HCl\rightarrow FeCl_2+H_2\)
           0,15    0,3                    0,15 
\(V_{H_2}=0,15.22,4=3,36l\\ m_{\text{dd}HCl}=\dfrac{100.\left(0,3.36,5\right)}{7,3}=150g\)

a) \(n_{Mg}=\dfrac{6}{24}=0,25\left(mol\right)\)

PTHH: Mg + H₂SO₄ --> MgSO₄ + H₂

           0,25----------------------->0,25

=> V_H2 = 0,25.22,4 = 5,6 (l)

b) 

\(n_{Fe_2O_3}=\dfrac{32}{160}=0,2\left(mol\right)\)

PTHH: Fe₂O₃ + 3H₂ --t^o--> 2Fe + 3H₂O

Xét tỉ lệ: \(\dfrac{0,2}{1}>\dfrac{0,25}{3}\) => H₂ hết

PTHH: Fe₂O₃ + 3H₂ --t^o--> 2Fe + 3H₂O

                           0,25----->\(\dfrac{1}{6}\)

=> \(m_{Fe}=\dfrac{1}{6}.56=\dfrac{28}{3}\left(g\right)\)

a) PTHH: \(Fe+2HCl\rightarrow FeCl_2+H_2\uparrow\)

b) Ta có: \(n_{HCl}=0,05\cdot0,3=0,015\left(mol\right)\)

\(\Rightarrow n_{Fe}=0,0075\left(mol\right)\) \(\Rightarrow m_{Fe}=0,0075\cdot56=0,42\left(g\right)\)

c+d) Theo PTHH: \(n_{FeCl_2}=n_{H_2}=n_{Fe}=0,0075\left(mol\right)\)

\(\Rightarrow\left\{{}\begin{matrix}V_{H_2}=0,0075\cdot22,4=0,168\left(l\right)\\m_{FeCl_2}=0,0075\cdot127=0,9525\left(g\right)\end{matrix}\right.\)

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

a.

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

\(V_{H_2}=24,79.0,2=4,958\left(l\right)\)

b.

\(n_{HCl}=2.n_{Fe}=0,4\left(mol\right)\\ CM_{HCl}=\dfrac{0,4}{0,2}=2M\)

1:

a) \(n_{Zn}=\dfrac{13}{65}=0,2\left(mol\right)\)

PTHH: \(Zn+H_2SO_4\rightarrow ZnSO_4+H_2\uparrow\)

______0,2------>0,2------------------->0,2_____(mol)

=> \(V_{H_2}=0,2.22,4=4,48\left(l\right)\)

b) \(V_{ddH_2SO_4}=\dfrac{0,2}{1}=0,2\left(l\right)\)

2:

a) 

\(n_{HCl}=2.0,2=0,4\left(mol\right)\)

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

______0,2<------0,4------------------>0,2______(mol)

=> \(m_{Mg}=0,2.24=4,8\left(g\right)\)

b) \(V_{H_2}=0,2.22,4=4,48\left(l\right)\)