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Why are nitric acid and hydrochloric acid not suitable for titration of sodium ethanadioate and potassium manganate (VII) solution?
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Why are nitric acid and hydrochloric acid not suitable for titration of sodium ethanadioate and potassium manganate (VII) solution?
As you may know, HCl is much stronger than Oxalic acid, it will react with KMnO4 to produce the corresponding chlorides of Potassium and Manganese along with liberation of Chlorine gas. This results in deficiency of total amount of KMnO4 available for the reaction with Oxalic acid, thereby affecting your redox titration.
As you may know, HCl is much stronger than Oxalic acid, it will react with KMnO4 to produce the corresponding chlorides of Potassium and Manganese along with liberation of Chlorine gas. This results in deficiency of total amount of KMnO4 available for the reaction with Oxalic acid, thereby affecting your redox titration.
This is because Nitric acid is oxidizing in nature just as potassium manganate (VII), end result will be erroneous. Hydrochloric acid on the other hand Hydrochloric acid will react (reduction) with potassium tetraoxomanganate (VII) and reduce it from Mn7+ to Mn2+, leading to another erroneous result. Dilute Tetraoxosulphate (VI) acid is an ideal acid for that redox titration as it does not alter the analyte or titrant.
This is because Nitric acid is oxidizing in nature just as potassium manganate (VII), end result will be erroneous. Hydrochloric acid on the other hand Hydrochloric acid will react (reduction) with potassium tetraoxomanganate (VII) and reduce it from Mn7+ to Mn2+, leading to another erroneous result. Dilute Tetraoxosulphate (VI) acid is an ideal acid for that redox titration as it does not alter the analyte or titrant.
The titration between sodium ethanedioate (sodium oxalate) and KMnO4 in the presence of a mineral acid is a redox reaction.
Nitric acid itself is a powerful oxidising agent, and so it will also react with and consume part of the oxalate ions. Therefore, in the presence of nitric acid, lesser amount of KMnO4 will be needed to reach the end point. On the other hand, hydrochloric acid (HCl) is a mild reducing agent, and so it will also consume a certain amount of KMnO4 during the titration. This will give a slightly higher value of KMnO4 consumption than the actual amount needed by the oxalate taken initially. Hence, both these two acids are avoided in redox reactions between other substances.
Dilute sulphuric acid is neither an oxidising agent, nor is it a reducing agent. So it is preferred in redox reactions involving KMnO4 or other oxidising agents.
The titration between sodium ethanedioate (sodium oxalate) and KMnO4 in the presence of a mineral acid is a redox reaction.
Nitric acid itself is a powerful oxidising agent, and so it will also react with and consume part of the oxalate ions. Therefore, in the presence of nitric acid, lesser amount of KMnO4 will be needed to reach the end point. On the other hand, hydrochloric acid (HCl) is a mild reducing agent, and so it will also consume a certain amount of KMnO4 during the titration. This will give a slightly higher value of KMnO4 consumption than the actual amount needed by the oxalate taken initially. Hence, both these two acids are avoided in redox reactions between other substances.
Dilute sulphuric acid is neither an oxidising agent, nor is it a reducing agent. So it is preferred in redox reactions involving KMnO4 or other oxidising agents.
Generally when creating an acidic medium for titration with KMnO4, the acid of choice is H2SO4 as the S is in a +6 oxidation state and cannot be further oxidised.
HCl is not used since the Cl- can be oxidised to give Cl2. Some KMnO4 will be reacted away as such and this would give you a higher than actual end point value.
Similarly, HNO3 is not used as HNO3 itself is also an oxidising agent. Ideally,in the titration reaction, you would want KMnO4 to be the only reactant that does the oxidation so that you can do the calculations with the titration values and obtain the accurate amount of ethanedioate present. If HNO3 is present, there is a possibility that it will oxidise the reactant before titration begins, leading to a lower than actual end point value.
Generally when creating an acidic medium for titration with KMnO4, the acid of choice is H2SO4 as the S is in a +6 oxidation state and cannot be further oxidised.
HCl is not used since the Cl- can be oxidised to give Cl2. Some KMnO4 will be reacted away as such and this would give you a higher than actual end point value.
Similarly, HNO3 is not used as HNO3 itself is also an oxidising agent. Ideally,in the titration reaction, you would want KMnO4 to be the only reactant that does the oxidation so that you can do the calculations with the titration values and obtain the accurate amount of ethanedioate present. If HNO3 is present, there is a possibility that it will oxidise the reactant before titration begins, leading to a lower than actual end point value.
As you may know, HCl is much stronger than Oxalic acid, it will react with KMnO4 to produce the corresponding chlorides of Potassium and Manganese along with liberation of Chlorine gas. This results in deficiency of total amount of KMnO4 available for the reaction with Oxalic acid, thereby affecting your redox titration.
The equation for the reaction is as given below:
KMnO4 + 16HCl ==> 2KCl + 2MnCl2 + 8H2O + 5Cl2
Hope this helps. All the best!
As you may know, HCl is much stronger than Oxalic acid, it will react with KMnO4 to produce the corresponding chlorides of Potassium and Manganese along with liberation of Chlorine gas. This results in deficiency of total amount of KMnO4 available for the reaction with Oxalic acid, thereby affecting your redox titration.
The equation for the reaction is as given below:
KMnO4 + 16HCl ==> 2KCl + 2MnCl2 + 8H2O + 5Cl2
Hope this helps. All the best!
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It is bcz KMnO4 act as oxidising agent only in acidic medium.so, inorder to provide acidic medium dilute sulphiric acid is added.
It is bcz KMnO4 act as oxidising agent only in acidic medium.so, inorder to provide acidic medium dilute sulphiric acid is added.
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This is because Nitric acid is oxidizing in nature just as potassium manganate (VII), end result will be erroneous. Hydrochloric acid on the other hand Hydrochloric acid will react (reduction) with potassium tetraoxomanganate (VII) and reduce it from Mn7+ to Mn2+, leading to another erroneous result. Dilute Tetraoxosulphate (VI) acid is an ideal acid for that redox titration as it does not alter the analyte or titrant.
This is because Nitric acid is oxidizing in nature just as potassium manganate (VII), end result will be erroneous. Hydrochloric acid on the other hand Hydrochloric acid will react (reduction) with potassium tetraoxomanganate (VII) and reduce it from Mn7+ to Mn2+, leading to another erroneous result. Dilute Tetraoxosulphate (VI) acid is an ideal acid for that redox titration as it does not alter the analyte or titrant.
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The titration between sodium ethanedioate (sodium oxalate) and KMnO4 in the presence of a mineral acid is a redox reaction.
Nitric acid itself is a powerful oxidising agent, and so it will also react with and consume part of the oxalate ions. Therefore, in the presence of nitric acid, lesser amount of KMnO4 will be needed to reach the end point. On the other hand, hydrochloric acid (HCl) is a mild reducing agent, and so it will also consume a certain amount of KMnO4 during the titration. This will give a slightly higher value of KMnO4 consumption than the actual amount needed by the oxalate taken initially. Hence, both these two acids are avoided in redox reactions between other substances.
Dilute sulphuric acid is neither an oxidising agent, nor is it a reducing agent. So it is preferred in redox reactions involving KMnO4 or other oxidising agents.
The titration between sodium ethanedioate (sodium oxalate) and KMnO4 in the presence of a mineral acid is a redox reaction.
Nitric acid itself is a powerful oxidising agent, and so it will also react with and consume part of the oxalate ions. Therefore, in the presence of nitric acid, lesser amount of KMnO4 will be needed to reach the end point. On the other hand, hydrochloric acid (HCl) is a mild reducing agent, and so it will also consume a certain amount of KMnO4 during the titration. This will give a slightly higher value of KMnO4 consumption than the actual amount needed by the oxalate taken initially. Hence, both these two acids are avoided in redox reactions between other substances.
Dilute sulphuric acid is neither an oxidising agent, nor is it a reducing agent. So it is preferred in redox reactions involving KMnO4 or other oxidising agents.
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Generally when creating an acidic medium for titration with KMnO4, the acid of choice is H2SO4 as the S is in a +6 oxidation state and cannot be further oxidised.
HCl is not used since the Cl- can be oxidised to give Cl2. Some KMnO4 will be reacted away as such and this would give you a higher than actual end point value.
Similarly, HNO3 is not used as HNO3 itself is also an oxidising agent. Ideally,in the titration reaction, you would want KMnO4 to be the only reactant that does the oxidation so that you can do the calculations with the titration values and obtain the accurate amount of ethanedioate present. If HNO3 is present, there is a possibility that it will oxidise the reactant before titration begins, leading to a lower than actual end point value.
Generally when creating an acidic medium for titration with KMnO4, the acid of choice is H2SO4 as the S is in a +6 oxidation state and cannot be further oxidised.
HCl is not used since the Cl- can be oxidised to give Cl2. Some KMnO4 will be reacted away as such and this would give you a higher than actual end point value.
Similarly, HNO3 is not used as HNO3 itself is also an oxidising agent. Ideally,in the titration reaction, you would want KMnO4 to be the only reactant that does the oxidation so that you can do the calculations with the titration values and obtain the accurate amount of ethanedioate present. If HNO3 is present, there is a possibility that it will oxidise the reactant before titration begins, leading to a lower than actual end point value.
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