(a)
Interpretation:
Three
Concept introduction:
The reaction in which both oxidation and reduction reaction occur simultaneously is called a redox reaction. According to the law of conservation of mass, the mass of all the species in a reaction must be balanced. Therefore balancing is necessary to conserve the mass and even the charge must be balanced to maintain the overall charge of the reaction.
(a)
Answer to Problem 31E
The balanced equations are as follows,
Explanation of Solution
The balanced equation is defined as follows,
The reduction half cell reaction is,
The change in the oxidation number of manganese is from
The oxidation half reaction is,
The change in oxidation number of aluminum is from zero to
As the atoms other than hydrogen and oxygen are already balanced, so directly balance the oxygen atom in the reduction half reaction by adding water to right hand side,
Balance the hydrogen atoms in the reduction half reaction by adding
Balance the charge by adding appropriate number of electrons to the left hand side,
As the atoms other than hydrogen and oxygen are already balanced in the oxidation half reaction. Therefore directly balance the oxygen by adding water molecule to the left hand side.
Balance the hydrogen atoms by adding
Balance the charge by adding electrons to the right hand side,
Add the oxidation and reduction half reaction to get the final equation,
Cancel similar terms on both the sides,
To balance the reaction in basic medium,
(b)
Interpretation:
Three oxidation-reduction reactions are given. The balancing of all the reactions in basic media using half-reaction method is to be done.
Concept introduction:
The reaction in which both oxidation and reduction reaction occur simultaneously is called a redox reaction. According to the law of conservation of mass, the mass of all the species in a reaction must be balanced. Therefore balancing is necessary to conserve the mass and even the charge must be balanced to maintain the overall charge of the reaction.
(b)
Answer to Problem 31E
The balanced equations are as follows,
Explanation of Solution
The balanced equation is defined as follows,
The reduction half cell reaction is,
The change in the oxidation number of chlorine is from zero to
The oxidation half reaction is,
The change in oxidation number of chlorine is from zero to
Balance all the atoms except hydrogen and oxygen in the reduction half reaction,
As there are no oxygen or hydrogen atoms in the reaction. So, directly balance the charge by adding appropriate number of electrons to the left hand side,
Balance all the atoms except hydrogen and oxygen in the oxidation half,
Balance the oxygen atom by adding water molecule to the left hand side,
Balance hydrogen atoms by adding
Balance the charge by adding electrons to the right hand side,
Add the oxidation and reduction half reaction,
Cancel similar terms on both the sides,
In basic medium,
Simplify the equation,
(c)
Interpretation:
Three oxidation-reduction reactions are given. The balancing of all the reactions in basic media using half-reaction method is to be done.
Concept introduction:
The reaction in which both oxidation and reduction reaction occur simultaneously is called a redox reaction. According to the law of conservation of mass, the mass of all the species in a reaction must be balanced. Therefore balancing is necessary to conserve the mass and even the charge must be balanced to maintain the overall charge of the reaction.
(c)
Answer to Problem 31E
The balanced equations are as follows,
Explanation of Solution
The balanced equation is defined as follows,
The reduction half cell reaction is,
The change in the oxidation number of nitrogen is from
The oxidation half reaction is,
The change in oxidation number of aluminum is from zero to
All the elements except hydrogen and oxygen are already balanced so directly balance the oxygen in the reduction half reaction by adding water to right hand side,
Balance the hydrogen atoms in the reduction half reaction by adding
Balance the charge by adding appropriate number of electrons to the left hand side,
All the atoms except hydrogen and oxygen in oxidation half reaction are already balanced. So, directly balance oxygen atom by adding water molecule to the left hand side,
Balance the hydrogen atom by adding
Balance the charge by adding electrons to the right hand side,
Multiply equation (6) by
Cancel similar terms on both the sides,
In basic medium,
The final equation is,
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Chapter 17 Solutions
Bundle: Chemistry: An Atoms First Approach, 2nd, Loose-Leaf + OWLv2, 4 terms (24 months) Printed Access Card
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