In the titration of KMnO4 and oxalic acid in acidic medium, the change in oxidation number of carbon at the end point is _____.
Correct Answer: 1
Approach Solution - 1
In the titration of potassium permanganate (KMnO4) and oxalic acid (H2C2O4) in an acidic medium, the oxidation number of carbon in oxalic acid changes. Initially, the oxidation state of carbon in oxalic acid is +3. During the reaction, oxalic acid is oxidized to carbon dioxide (CO2), where carbon has an oxidation number of +4. This represents an increase in the oxidation number by 1. Therefore, the change in the oxidation number of carbon at the endpoint of the titration is +1. The computed change, +1, falls within the specified range of 1,1, confirming the solution is correct.
Approach Solution -2
\(16H^++2MnO^-_4+5C_2O^{2-}_4→10CO_2+2Mn_{2+}+8H_2O\)
During titration of oxalic acid by KMnO4, oxalic acid converts into CO2.
∴ Change in oxidation state of carbon = 1
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