\(n_{Al}=\dfrac{2,7}{27}=0,1mol\\ a.2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)

0,1           0,15               0,05               0,15

\(b.V_{H_2}=0,15.24,79=3,7185l\\ c.m_{Al_2\left(SO_4\right)_3}=0,05.342=17,1g\\ d.C_{M_{H_2SO_4}}=\dfrac{0,15}{0,4}=0,375M\)

D

\(4.a/n_{Al}=\dfrac{5,4}{27}=0,2mol\\ 2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)

0,2       0,3                  0,1                  0,3

\(V_{H_2}=0,3.24,79=7,437l\\ b/C_{\%H_2SO_4}=\dfrac{0,3.98}{150}\cdot100=19,6\%\\ c/m_{Al_2\left(SO_4\right)_3}=0,1.342=34,2g\)

\(5.a/n_{MgO}=\dfrac{4}{40}=0,1mol\\ MgO+2HCl\rightarrow MgCl_2+H_2O\)

0,1            0,2             0,1              0,1

\(C_{\%HCl}=\dfrac{0,2.36,5}{200}\cdot100=3,65\%\\ b/C_{\%MgCl_2}=\dfrac{0,1.95}{200+4}\cdot100=4,66\%\\ c/NaOH+HCl\rightarrow NaCl+H_2O\\ n_{NaOH}=n_{HCl}=0,2mol\\ V_{NaOH}=\dfrac{0,2}{1}=0,2l=200ml\)

\(n_{Zn}=\dfrac{3,25}{65}=0,05mol\)

\(Zn+2HCl\rightarrow ZnCl_2+H_2\)

0,05    0,1                      0,05            ( mol )

\(V_{H_2}=0,05.22,4=1,12l\)

\(m_{HCl}=0,1.36,5=3,65g\)

\(Fe_3O_4+4H_2\rightarrow\left(t^o\right)3Fe+4H_2O\)

                0,05           0,0375              ( mol )

\(m_{Fe}=0,0375.56=2,1g\)

\(4.\\ a/n_{Al}=\dfrac{5,4}{27}=0,2mol\\2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)

\(0,2......0,3............0,1...............0,3\)

\(V_{H_2}=0,3.24,79=7,437l\\ b.C_{\%H_2SO_4}=\dfrac{0,3.98}{150}\cdot100=19,6\%\\ c.m_{Al_2\left(SO_4\right)_3}=0,1.342=34,2g\)

\(7.\\a) n_{H_2SO_4}=\dfrac{100.9,8}{100.98}=0,1mol\\ ZnO+H_2SO_4\rightarrow ZnSO_4+H_2O\\ n_{ZnO}=n_{ZnSO_4}=n_{H_2SO_4}=0,1mol\\ m_{ZnO}=0,1.81=8,1g\\ b)C_{\%ZnSO_4}=\dfrac{0,1.161}{8,1+100}\cdot100=14,8\%\)

\(9.\\ a)n_{H_2}=\dfrac{2,479}{24,79}=0,1mol\\ Mg+2HCl\rightarrow MgCl_2+H_2\)

\(0,1.....0,2.........0,1........0,1\)

\(m_{Mg}=0,1.24=2,4g\\ m_{MgO}=8,4-2,4=6g\\ b)n_{MgO}=\dfrac{6}{40}=0,15mol\\ MgO+2HCl\rightarrow MgCl_2+H_2O\\ n_{HCl}=0,15.2+0,2=0,5mol\\ m_{ddHCl}=\dfrac{0,5.36,5}{3,65}\cdot100=500g\)

2Al+6HCl->2AlCl₃+3H₂

0,2----0,6-----0,2-----0,3 mol

n _H2=\(\dfrac{7,437}{24,79}\)=0,3 mol

=>m_Al=0,2.27=5,4g

=>m _HCl=0,6.36,5=21,9g

=>m _AlCl3=0,2.133,5=26,7g

3H2+Fe₂O₃-to>2Fe+3H₂O

0,3-------0,1----------0,2 mol

=>m _Fe=0,2.56=11,2g

=>m_Fe2O3=0,1.160=16g

nH2 = 7,437/24,79 = 0,3 (mol)

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

Mol: 0,2 <--- 0,6 <--- 0,2 <--- 0,3

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

mHCl = 0,6 . 36,5 = 21,9 (g)

mAlCl3 = 0,2 . 204,5 = 40,9 (g)

PTHH: Fe2O3 + 3H2 -> (t°) 2Fe + 3H2O

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

mFe2O3 = 0,1 . 160 = 16 (g)

a. \(n_{H_2}=\dfrac{7.437}{24,79}=0,3\left(mol\right)\)

PTHH : 2Al + 6HCl -> 2AlCl₃ + 3H₂ 

              0,2      0,6                  0,3

\(m_{Al}=0,2.27=5,4\left(g\right)\)

\(m_{HCl}=0,6.36,5=21,9\left(g\right)\)

a, \(Fe+2HCl\rightarrow FeCl_2+H_2\)

\(n_{H_2}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\)

Theo PT: \(n_{Fe}=n_{H_2}=0,15\left(mol\right)\Rightarrow m_{Fe}=0,15.56=8,4\left(g\right)\)

\(n_{HCl}=2n_{H_2}=0,3\left(mol\right)\Rightarrow m_{HCl}=0,3.36,5=10,95\left(g\right)\)

b, \(n_{FeCl_2}=n_{H_2}=0,15\left(mol\right)\Rightarrow m_{FeCl_2}=0,15.127=19,05\left(g\right)\)

\(a/n_{H_2}=\dfrac{3,36}{22,4}=0,15mol\\ Fe+2HCl\rightarrow FeCl_2+H_2\)

0,15       0,3           0,15          0,15

\(m_{Fe}=0,15.56=8,4g\\ m_{HCl}=0,3.36,5=10,95g\\ b/m_{FeCl_2}=0,15.127=19,05g\)

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

0,15   0,3          0,15       0,15

\(n_{H_2}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\)

\(a,m_{Fe}=0,15.56=8,4\left(g\right)\)

\(m_{HCl}=0,3.36,5=10,95\left(g\right)\)

\(b,m_{FeCl_2}=0,15.127=19,05\left(g\right)\)

\(a.n_{Fe}=\dfrac{8,4}{56}=0,15mol\)

\(Fe+2HCl\rightarrow FeCl_2+H_2\\ n_{Fe}=n_{H_2}=n_{FeCl_2}=0,15mol\\ V_{H_2,đktc}=0,15.22,4=3,36l\\ V_{H_2,đkc}=0,15.24,79=3,7185l\\ b.n_{HCl}=0,15.2=0,3mol\\ C_{M_{HCl}}=\dfrac{0,3}{0,2}=1,5M\\ c.m_{FeCl_2}=0,15.127=19,05g\)

a, \(Zn+2HCl\rightarrow ZnCl_2+H_2\)

b, \(n_{Zn}=\dfrac{39}{65}=0,6\left(mol\right)\)

Theo PT: \(n_{HCl}=2n_{Zn}=1,2\left(mol\right)\Rightarrow m_{HCl}=1,2.36,5=43,8\left(g\right)\)

c, \(n_{H_2}=n_{Zn}=0,6\left(mol\right)\Rightarrow V_{H_2}=0,6.24,79=14,874\left(l\right)\)

d, - Quỳ tím hóa đỏ do HCl dư.

\(a.2Al+6HCl->2AlCl_3+3H_2\\ b.m_{AlCl_3}=\dfrac{1}{3}.0,1.0,6.133,5=2,67g\\ c.V_{H_2}=\dfrac{1}{2}.0,06.24,79=0,7437\left(L\right)\\ d.a=\dfrac{1}{3}.0,1.0,6.27=0,54g\)