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
Indicator
KMnO4 is a self-indicator.
Endpoint
Colourless to permanent pink colour (KMnO4 in burette).
Procedure
- Rinse and fill the burette with the given KMnO4 solution.
- 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. - Add one test tube (~ 20 ml) full of dilute sulphuric acid (~ 4 N) to the solution in , titration flask.
- Note the initial reading of the burette.
- 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.
- Note the final reading of the burette.
- Repeat the above steps 4-5 times to get three cdncordant readings.
Observations
CALCULATIONS