In the titration of KMnO _ 4 and oxalic acid in acidic medium, the...

The balanced equation of potassium permanganate and oxalic acid reaction in acidic medium is shown below.

$2K\overset{+ 7}{Mn}{O}_{4} + 5{H}_{2}\overset{+ 3}{{C}_{2}}{O}_{4} + 3{H}_{2}{SO}_{4}\left(dil .\right) \to {K}_{2}{SO}_{4} + 2\overset{+ 2}{M}{nSO}_{4} + 10\overset{+ 4}{C}{O}_{2} + 8{H}_{2}O$

The initial oxidation state of carbon in the oxalic acid is $+ 3$. The oxidation state of carbon at the end point is $+ 4$(in carbon dioxide). Hence, the change in oxidation state of carbon at the end point is 1.