Respuesta :
Explanation :
Redox reaction or Oxidation-reduction reaction : It is defined as the reaction in which the oxidation and reduction reaction takes place simultaneously.
Oxidation reaction : It is defined as the reaction in which a substance looses its electrons. In this, oxidation state of an element increases. Or we can say that in oxidation, the loss of electrons takes place.
Reduction reaction : It is defined as the reaction in which a substance gains electrons. In this, oxidation state of an element decreases. Or we can say that in reduction, the gain of electrons takes place.
(a) The balanced chemical reaction will be:
[tex]2Al+3F_2\rightarrow 2AlF_3[/tex]
The oxidation-reduction half reaction will be :
Oxidation : [tex]Al\rightarrow Al^{3+]+3e^-[/tex]
Reduction : [tex]F_2+2e^-\rightarrow 2F^-[/tex]
In this reaction, the oxidation state of 'Al' changes from (0) to (+3) that means 'Al' lost 3 electron and it shows oxidation and the oxidation state of 'F' changes from (0) to (-1) that means 'F' gains 1 electron and it shows reduction.
In this reaction, aluminum is the oxidizing atom that has the highest oxidation state is (+3).
(b) The balanced chemical reaction will be:
[tex]Al+CuBr_2\rightarrow AlBr_2+Cu[/tex]
The oxidation-reduction half reaction will be :
Oxidation : [tex]Al\rightarrow Al^{3+}+3e^-[/tex]
Reduction : [tex]Cu^{2+}+2e^-\rightarrow Cu[/tex]
In this reaction, the oxidation state of 'Al' changes from (0) to (+3) that means 'Al' lost 3 electrons and it shows oxidation and the oxidation state of 'Cu' changes from (+2) to (0) that means 'Cu' gains 2 electron and it shows reduction.
In this reaction, aluminum is the oxidizing atom that has the highest oxidation state is (+3).
(c) The balanced chemical reaction will be:
[tex]P_4+5O_2\rightarrow 2P_2O_5[/tex]
The oxidation-reduction half reaction will be :
Oxidation : [tex]P_4\rightarrow P^{5+}+5e^-[/tex]
Reduction : [tex]O_2+2e^-\rightarrow O^{2-}[/tex]
In this reaction, the oxidation state of 'P' changes from (0) to (+5) that means 'P' lost 5 electron and it shows oxidation and the oxidation state of 'O' changes from (0) to (-2) that means 'O' gains 2 electron and it shows reduction.
In this reaction, phosphorous is the oxidizing atom that has the highest oxidation state is (+5).
(d) The balanced chemical reaction will be:
[tex]Ca+H_2O\rightarrow Ca(OH)_2+H_2[/tex]
The oxidation-reduction half reaction will be :
Oxidation : [tex]Ca\rightarrow Ca^{2+}+2e^-[/tex]
Reduction : [tex]2H^{+}+2e^-\rightarrow H_2[/tex]
In this reaction, the oxidation state of 'Ca' changes from (0) to (+2) that means 'Ca' lost 2 electrons and it shows oxidation and the oxidation state of 'H' changes from (+1) to (0) that means 'H' gains 2 electron and it shows reduction.
In this reaction, calcium is the oxidizing atom that has the highest oxidation state is (+2).
