Write a practical on prepare standard solution of M /40 oxalic acid solution.
Dear student,
Aim- To prepare 100 ml of M/40 solution of oxalic acid.
APPARATUS AND CHEMICALS REQUIRED- Oxalic acid, weighing bottle, weight box, volumetric flask, funnel, distilled water, chemical balance, beakers, conical flask, funnel, burette, pipette, clamp stand, tile, dilute H2SO4, KMnO4 solution.
Procedure-
a) Weigh a clean dry bottle using a chemical balance.
b) Add 3.15g more weights to the pan containing the weights for the weighing bottle.
c) Add oxalic acid in small amounts to the weighing bottle, so that the pans are balanced.
d) Remove the weighing bottle from the pan.
e) Using a funnel, transfer the oxalic acid to the volumetric flask.
f) Add a few drops of distilled water to dissolve the oxalic acid.
g) Make up the volume to the required level using distilled water
h) The standard solution is prepared.
Theory- Oxalic acid is a dicarboxylic acid having molar mass 126g/mol. It is a primary standard and has the molecular formula COOH-COOH.2H2O. Its equivalent mass is 126/2 = 63 as its n factor is 2.
1) The reaction between KMnO4 and oxalic acid is a redox reaction and the titration is therefore called a redox titration.
2) Oxalic acid is the reducing agent and KMnO4 is the oxidizing agent.
3) KMnO4 acts as an oxidizing agent in all the mediums i.e. acidic, basic and neutral medium.
4) KMnO4 acts as the strongest oxidizing agent in the acidic medium and therefore dil. H2SO4 is added to the conical flask before starting the titration.
5) The titration between oxalic acid and KMnO4 is a slow reaction, therefore heat the oxalic acid solution to about 600 C to increase the rate of the reaction.
Procedure-
1) Fill the burette with KMnO4 solution
2) Pipette out 10ml. of oxalic acid solution into the conical flask.
3) Add half a test tube of dil. H2SO4 and heat the solution to about 600 to increase the rate of the reaction.
4) Keep a glazed tile under the burette and place the conical flask on it.
5) Note down the initial reading of the burette.
6) Run down the KMnO4 solution into the conical flask dropwise with shaking.
7) Stop the titration when a permanent pink colour is obtained in the solution.
8) This is the endpoint. Note down the final burette reading.
9) Repeat the experiment until three concordant values are obtained.
Regards
Aim- To prepare 100 ml of M/40 solution of oxalic acid.
APPARATUS AND CHEMICALS REQUIRED- Oxalic acid, weighing bottle, weight box, volumetric flask, funnel, distilled water, chemical balance, beakers, conical flask, funnel, burette, pipette, clamp stand, tile, dilute H2SO4, KMnO4 solution.
Procedure-
a) Weigh a clean dry bottle using a chemical balance.
b) Add 3.15g more weights to the pan containing the weights for the weighing bottle.
c) Add oxalic acid in small amounts to the weighing bottle, so that the pans are balanced.
d) Remove the weighing bottle from the pan.
e) Using a funnel, transfer the oxalic acid to the volumetric flask.
f) Add a few drops of distilled water to dissolve the oxalic acid.
g) Make up the volume to the required level using distilled water
h) The standard solution is prepared.
Theory- Oxalic acid is a dicarboxylic acid having molar mass 126g/mol. It is a primary standard and has the molecular formula COOH-COOH.2H2O. Its equivalent mass is 126/2 = 63 as its n factor is 2.
1) The reaction between KMnO4 and oxalic acid is a redox reaction and the titration is therefore called a redox titration.
2) Oxalic acid is the reducing agent and KMnO4 is the oxidizing agent.
3) KMnO4 acts as an oxidizing agent in all the mediums i.e. acidic, basic and neutral medium.
4) KMnO4 acts as the strongest oxidizing agent in the acidic medium and therefore dil. H2SO4 is added to the conical flask before starting the titration.
5) The titration between oxalic acid and KMnO4 is a slow reaction, therefore heat the oxalic acid solution to about 600 C to increase the rate of the reaction.
Procedure-
1) Fill the burette with KMnO4 solution
2) Pipette out 10ml. of oxalic acid solution into the conical flask.
3) Add half a test tube of dil. H2SO4 and heat the solution to about 600 to increase the rate of the reaction.
4) Keep a glazed tile under the burette and place the conical flask on it.
5) Note down the initial reading of the burette.
6) Run down the KMnO4 solution into the conical flask dropwise with shaking.
7) Stop the titration when a permanent pink colour is obtained in the solution.
8) This is the endpoint. Note down the final burette reading.
9) Repeat the experiment until three concordant values are obtained.
Regards