Standardization of NaOH Solution Using Oxalic Acid

            
             In this experiment you will be assessed on Data Collection, Data Analysis and Evaluation.
            
             To determine the molarity of an NaOH solution by titrating it with Oxalic acid (a primary standard).
             Introduction: .
             Oxalic acid is a primary standard. It can therefore be used to determine the molarity of an NaOH solution.
             Oxalic acid is a weak acid. Therefore this is an example of a weak acid-strong alkali titration and the indicator is phenolphthalein.
             You should be aware that oxalic acid and oxalates are EXTREMELY POISONOUS AND CAR SHOULD BE EXERCISED. Ensure that you wash your hands after the experiment and especially before eating anything. In addition oxalic acid is not very soluble and will require the use of a glass rod to dissolve it. Ensure that you do not add more then the required volume of water in this process.
             Apparatus:.
             á× 25ml Pipette.
             á× 50 ml Burette.
             á× Beaker.
             á× 250ml Volumetric Flask.
             á× Conical Flask.
             á× Distilled Water.
             á× Electronic Balance.
             á× Glass Rod.
             á× Clamp Stand.
             á× Oxalic acid.
             á× .1mole/dm ©Ã¸ solution of NaOH.
             á× Phenolphthalein (indicator).
             Method:.
             1. With the aid of an electronic balance weigh out 1.575g of hydrated Oxalic acid.
             2. Dissolve the Oxalic acid in a beaker with distilled water and with the aid of a glass rod.
             3. When the Oxalic acid has completely dissolved then transfer the solution into a volumetric flask and make a 250ml solution using distilled water.
             4. Transfer this solution into the 50ml burette .
             5. Shake the volumetric flask thoroughly to make sure the solution is homogeneous. .
             6. With the aid of a 25ml pipette measure out exactly 25ml of the 0.1M NaOH and transfer it into a clean conical flask.
             7. Add 2-3 drops of Phenolphthalein indicator.
             8. Titrate the solution until the indictor color changes from purple to color less. (Titrate to 1-drop accuracy).
             9. Repeat to obtain 3 concordant results.