a: \(Cu+H_2SO_4->CuSO_4+H_2\)

\(CuSO_4+BaCl_2->CuCl_2+BaSO_4\)

\(2CuCl_2+O_2->2CuO+2Cl_2\)

a. 

\(\left(1\right)Fe+2HCl--->FeCl_2+H_2\)

\(\left(2\right)FeCl_2+2NaOH--->2NaCl+Fe\left(OH\right)_2\)

\(\left(3\right)4Fe\left(OH\right)_2+O_2+2H_2O\overset{t^o}{--->}4Fe\left(OH\right)_3\)

\(\left(4\right)2Fe\left(OH\right)_3\overset{t^o}{--->}Fe_2O_3+3H_2O\)

\(\left(5\right)Fe_2O_3+6HCl--->2FeCl_3+3H_2O\)

b.

\(\left(1\right)4Al+3O_2\overset{t^o}{--->}2Al_2O_3\)

\(\left(2\right)Al_2O_3+6HCl--->2AlCl_3+3H_2O\)

\(\left(3\right)AlCl_3+3NaOH--->Al\left(OH\right)_3+3NaCl\)

\(\left(4\right)2Al\left(OH\right)_3\overset{t^o}{--->}Al_2O_3+3H_2O\)

\(\left(5\right)Al_2O_3+3H_2SO_4--->Al_2\left(SO_4\right)_3+3H_2O\)

\(b,\left(1\right)4Al+3O_2\rightarrow^{t^o}2Al_2O_3\\ \left(2\right)Al_2O_3+6HCl\rightarrow2AlCl_3+3H_2O\\ \left(3\right)AlCl_3+3NaOH\rightarrow Al\left(OH\right)_3+3NaCl\\ \left(4\right)2Al\left(OH\right)_3\rightarrow^{t^o}Al_2O_3+3H_2O\\ \left(5\right)Al_2O_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2O\)

\(a,\left(1\right)Fe+2HCl\rightarrow FeCl_2+H_2\\ \left(2\right)FeCl_2+2NaOH\rightarrow Fe\left(OH\right)_2+2NaCl_2\\ \left(3\right)4Fe\left(OH\right)_2+O_2+2H_2O\rightarrow4Fe\left(OH\right)_3\\ \left(4\right)2Fe\left(OH\right)_3\rightarrow^{t^o}Fe_2O_3+3H_2O\\ \left(5\right)Fe_2O_3+6HCl\rightarrow2FeCl_3+3H_2O\)

(1) \(2Al\left(OH\right)_3\underrightarrow{t^o}Al_2O_3+3H_2O\)

(2) \(Al_2O_3+3H_2SO_4->Al_2\left(SO_4\right)_3+3H_2O\)

(3) \(Al_2\left(SO_4\right)_3+3BaCl_2->3BaSO_4\downarrow+2AlCl_3\)

Al+H2SO4 -> Al2(SO4)3+ H2 \(\uparrow\)

Al2(SO4)3 +HCl -> AlCl3+ H2SO4

AlCl3 +Ca(OH)2 -> Al(OH)3 +CaCl2 

Al(OH)3 - to> Al2O3 +H20

\(2Al+3H_2SO_4\to Al_2(SO_4)_3+3H_2\\ Al_2(SO_4)_3+3BaCl_2\to 3BaSO_4\downarrow+2AlCl_3\\ AlCl_3+3NaOH\to Al(OH)_3\downarrow+3NaCl\\ 2Al(OH)_3\xrightarrow{t^o} Al_2O_3+3H_2O\)

Al+H2SO4 -> Al2(SO4)3+ H2 

↑

Al2(SO4)3 +HCl -> AlCl3+ H2SO4

AlCl3 +Ca(OH)2 -> Al(OH)3 +CaCl2 

Al(OH)3 - to> Al2O3 +H20

4Al+3O₂----t^o--->2Al₂O₃

Al₂O₃ +3H₂SO₄----->Al₂(SO₄)₃+3H₂O

Al₂(SO₄)₃+3BaCl₂------>2AlCl₃+3BaSO₄

2AlCl₃+3Ca(OH)₂---->2Al(OH)₃+3CaCl₂

Al(OH)₃+3HNO₃---->Al(NO₃)₃+3H₂O

2Al(NO₃)₃+3Mg----->3Mg(NO₃)₂+2Al

2Al+3H₂SO₄------->Al₂(SO₄)₃+3H₂

Al₂(SO₄)₃+3Ca(OH)₂------>2Al(OH)₃+3CaSO₄

2Al(OH)₃-----t^o----->Al₂O₃+3H₂O

2Al₂O₃----\(\dfrac{t^o}{criolit}\)---->4Al+3O₂

2Al+2H₂O+2NaOH------>2NaAlO₂+3H₂

4Al+3O₂\(\underrightarrow{t^o}\) 2Al₂O₃

Al₂O₃+H₂SO₄ —> Al₂(SO₄)₃+3H₂O

Al₂(SO₄)₃+3BaCl₂–>3BaSO₄\(\downarrow\)+2AlCl₃

AlCl₃+3NaOH—>Al(OH)₃\(\downarrow\)+3NaCl

Al(OH)₃+HNO₃ —>Al(NO₃)₃+NO₂\(\uparrow\)+H₂O

2Al(NO₃)₃+3Mg—>3Mg(NO₃)₂+2Al\(\downarrow\)

2Al+3H₂SO₄–>Al₂(SO₄)₃+3H₂\(\uparrow\)

Al₂(SO₄)₃+6NaOH—>2Al(OH)₃+3Na₂SO₄

2Al(OH)₃\(\underrightarrow{t^o}\)Al₂O₃+3H₂O

2Al₂O₃\(\xrightarrow[criolit]{đien.phan.nong.chay}\)

4Al+3O₂

2Al+2NaOH+2H₂O—>2NaAlO₂+3H₂

\(\begin{array}{l} 4Al+3O_2\xrightarrow{t^o} 2Al_2O_3\\ Al_2O_3+3H_2SO_4\to Al_2(SO_4)_3+3H_2O\\ Al_2(SO_4)_3+3BaCl_2\to 3BaSO_4\downarrow+2AlCl_3\\ AlCl_3+3NaOH\to Al(OH)_3\downarrow+3NaCl\\ Al(OH)_3+3HNO_3\to Al(NO_3)_3+3H_2O\\ 2Al(NO_3)_3+3Mg\to 3Mg(NO_3)_2+2Al\\ 2Al+3H_2SO_4\to Al_2(SO_4)_3+3H_2\uparrow\\ Al_2(SO_4)_3+6NaOH\to 2Al(OH)_3\downarrow+3Na_2SO_4\\ 2Al(OH)_3\xrightarrow{t^o} Al_2O_3+3H_2O\\ 2Al_2O_3\xrightarrow{\text{đpnc, Criolit}} 4Al+3O_2\uparrow\\ 2Al+2NaOH+2H_2O\to 2NaAlO_2+3H_2\uparrow\end{array}\)