How to prepare and Standardize 0.05 N Sulphuric acid volumetric Solution

How to prepare and Standardize 0.05 N Sulphuric acid volumetric Solution

                                                 

                                                      

Preparation of 0.05 N Sulphuric acid volumetric solution.

➤ Glass ware and instruments required.

Beaker, Glass stirrer, Graduated Pipettes, Graduated cylinder, Analytical balance, Sucker, Volumetric flask, Burette, Conical Flask, Fume hood.

➤ Reagents required.

Sulphuric acid.
Molecular wt H2SO4 , 98.08
Sodium carbonate primary standard. (Previously dried for 1 hour at 270°C - 300°C)
Methyl red indicator.

 ➤ Preparation.

Transfer slowly with stirring, 0.3 ml of sulphuric acid reagent grade to 1000 ml volumetric flask containing 100 ml water, cool and dilute up to the mark with same solvent.

➤ Standardisation.

Accurately weigh about 0.015 g sodium carbonate PS, previously dried for 1 hour at 270° - 300°, in 250 ml conical flask. Dissolve in 100 ml water. Add 2 drops of methyl red indicator solution. Titrate with 0.01 N / 0.005 M sulphuric acid till the solution becomes faint pink. Heat the solution to boiling, cool to room temperature by holding the flask under tap water. Continue titration to faint pink colour. Repeat the steps of heating and cooling till faint pink colour is restored. 

➤ Calculations.

                            Wt. of  Na2CO3  × 0.05  
Normality = --------------------------------------------
                         0.0005299 × Burette reading in mL