Preparation and Standardization of 0.25 M Ethanolic Sulphuric Acid

Ethanolic Sulphuric Acid Solution Preparation

• Add slowly, with stirring, 13.9 ml of sulphuric acid to 900 ml ethanol.
• Make up the volume with ethanol to produce 1000 ml.
• Allow the solution to cool down.
• Standardize the solution before use.

Ethanolic Sulphuric Acid Solution Standardization

• Weigh accurately about 800 mg of anhydrous sodium carbonate, previously heated at about 270 °C for 1 hour.
• Dissolve it in 100 ml of water and add 0.1 ml of methyl red solution.
• Add the acid slowly from a burette, with constant stirring, until the solution becomes faintly pink. Heat the solution to boiling, cool and continue the titration. Heat again to boiling and titrate further as necessary until the faint pink color is no longer affected by continued boiling.
• 1 ml of 1 M hydrochloric acid is equivalent to 0.05299 g of Na2CO3.

Calculation

                      Na2CO3 in gm
M = -----------------------------------------
       Volume of H2SO4 in ml x 52.99
Also see: Determination of Shelf Life of Solutions in Laboratory