Prepare N/20 solution of oxalic acid. Using this solution, find out strength and normality of the given potassium permanganate solution 

Prepare N/20 solution of oxalic acid. Using this solution, find out strength and normality of the given potassium permanganate solution.

Chemical equations
prepare-n20-solution-of-oxalic-acid-using-this-solution-find-out-strength-and-normality-of-the-given-potassium-permanganate-solution-1

Indicator
KMnO4 is a self-indicator.

Endpoint
Colourless to permanent pink colour (KMnO4 in burette).

Procedure

  1. Rinse and fill the burette with the given KMnO4 solution.
  2. Weigh exactly 1.58 g of oxalic acid crystals and dissolve in water to prepare 500 ml of
    its solution using a 500 ml measuring flask. Rinse the pipette with the N/20 oxalic acid
    solution and pipette out 20 ml of it in a washed titration flask.
  3. Add one test tube (~ 20 ml) full of dilute sulphuric acid (~ 4 N) to the solution in , titration flask.
  4. Note the initial reading of the burette.
  5. Heat the flask to 60-70°C and add KMnO4 solution from the burette till a permanent light pink colour is just imparted to the solution in the titration flask.
  6. Note the final reading of the burette.
  7. Repeat the above steps 4-5 times to get three cdncordant readings.

Observations 
prepare-n20-solution-of-oxalic-acid-using-this-solution-find-out-strength-and-normality-of-the-given-potassium-permanganate-solution-2

CALCULATIONS
prepare-n20-solution-of-oxalic-acid-using-this-solution-find-out-strength-and-normality-of-the-given-potassium-permanganate-solution-3

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