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A mixture of oxalic acid (H2C2O4) and potassium oxalate (K2C2O4) required 25 mL of 0.2 N KMnO4 solution for complete oxidation. The same mixture required 20 mL of 0.2 M NaOH solution for complete neutralization. Calculate the mole percentage of H2C2O4 in the mixture. Express your answer as a single digit obtained by repeatedly summing the digits of the numerical result.
- 6
- 7
- 8
- 9
Correct answer: 8
Solution
KMnO4 gives total oxalate = 2.5 mmol; NaOH gives H2C2O4 = 2 mmol; mole% = 80%; digit sum of 80 = 8.
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