\[2 \ce{KMnO4 (aq) + 5 Na2C2O4 (aq) + 8 H2SO4 (aq) -> 2 MnSO4 (aq) + 10 CO2 (g) + K2SO4 (aq) + 5 Na2SO4 (aq) A student is planning on doing a redox titration involving theabove chemical reaction. The first step the student must perform is to standardize the \(\ce{KMnO4}\) solution (approximately 0.1 M ) with primary standard sodium oxalate (molar mass 134.0 g mol-1). The student carefully weighs 5.360 g of \(\ce{Na2C2O4}\) into a flask and adds about 25 mL of distilled water to dissolve the sample and 50.00 mL of 1.000 M \(\ce{H2SO4}\) to the flask. The \(\ce{Na2C2O4}\) solution is then titrated with the \(\ce{KMnO4}\) . This titration requires 40.00 mL of the \(\ce{KMnO4}\) solution. From this information, the student calculates the molarity. The student carefully repeats this procedure three more times and averages the consistent results of the four titrations. However, when the standardized \(\ce{KMnO4}\) solution is used to determine the amount of \(\ce{Na2C2O4}\) in an unknown, the results are inaccurate. What did the student do wrong?

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