Question

viết các phương trình sau:
a, Al-->Al2O3-->Al2(SO4)3-->Al(OH)3-->Al2O3

b, Fe-->Fe2O3-->Fe2(SO4)3-->Fe(OH)3-->Fe2O3-->FeCl3

Answer 1

a.

(1) 4Al + 3O₂ ---> 2Al₂O₃

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

(3)\(Al_2\left(SO_4\right)_3+6NaOH\rightarrow2Al\left(OH\right)_3\downarrow+3Na_2SO_4\)

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

Answer 2

a, 4Al + 3O₂ -> 2Al₂O₃

Al₂O₃ + 3H₂SO₄ -> Al₂(SO₄)₃ + 3H₂O

Al₂(SO₄)₃ + 6NaOH -> 2Al(OH)₃ + 3Na₂SO₄

2Al(OH)₃ nhiệt độ lên Al₂O₃ + 3H₂O

b, 4Fe + 3O₂ -> 2Fe₂O₃

Fe₂O₃ + 3H₂SO₄ -> Fe₂(SO₄)₃ + 3H₂O

Fe₂(SO₄)_{3 + KOH -> Fe(OH)3}

_{Fe(OH)3 nhiệt độ lên Fe2O3 + h20}

_{Fe2O3 + 6HCl -> 2FeCl3 + 3H2o}

Answer 3

a)

4Al+3O₂\(\overset{t^0}{\rightarrow}2Al_2O_3\)

Al₂O₃+3H₂SO₄\(\rightarrow\)Al₂(SO₄)₃+3H₂O

Al₂(SO₄)₃+6NaOH\(\rightarrow\)2Al(OH)₃\(\downarrow\)+3Na₂SO₄

2Al(OH)₃\(\overset{t^0}{\rightarrow}Al_2O_3+3H_2O\)

Answer 4

b)

4Fe+3O₂\(\rightarrow\)2Fe₂O₃(oxi nguyên chất)

Fe₂O₃+3H₂SO₄\(\rightarrow\)Fe₂(SO₄)₃+3H₂O

Fe₂(SO₄)₃+6NaOH\(\rightarrow\)2Fe(OH)₃+3Na₂SO₄

2Fe(OH)₃\(\overset{t^0}{\rightarrow}Fe_2O_3+3H_2O\)

Fe₂O₃+6HCl\(\rightarrow\)2FeCl₃+3H₂O

Answer 5

(1) \(4Fe+3O_2\rightarrow2Fe_2O_3\)

(2) \(Fe_2O_3+3H_2SO_4\rightarrow Fe_2\left(SO_4\right)_3+3H_2O\)

(3) \(Fe_2\left(SO_4\right)_3+6KOH\rightarrow3K_2SO_4+2Fe\left(OH\right)_3\downarrow\)

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

(5) \(Fe_2O_3+6HCl\rightarrow2FeCl_3+3H_2O\)

P/s: \(\downarrow\) là kết tủa nha (trong SGK ghi là (r))

Answer 6

a, 4Al+3O2---> 2Al2O3

Al2O3+3H2SO4---> Al2(SO4)3+3H2O

Al2(SO4)3+6NaOH---> 2Al(OH)3+3Na2SO4

2Al(OH)3--t^o--> Al2O3+3H2O

b, 4Fe+3O2--->2Fe2O3

Fe2O3+3H2SO4---> Fe2(SO4)3+3H2O

Fe2(SO4)3+6NaOH--->2Fe(OH)3+3Na2SO4

2Fe(OH)3--t^o--> Fe2O3+3H2O

Fe2O3+6HCl---> 2FeCl3+3H2O