Preparation and Standardization of 0.1 M Hydrochloric acid (HCl)

Hydrochloric acid Solution Preparation

• Take about 100 ml of water in a cleaned and dried 1000 ml volumetric flask.
• Add about 8.5 ml of Conc. Hydrochloric acid with continuous stirring. 
• Add more about 700 ml of water, mix and allow to cool to room temperature. 
• Make up the volume 1000 ml with water. Mix solution thoroughly. 
• Keep the solution for at least one hour and then carry out the standardization.

Related: Determination of Shelf Life of Solutions in Laboratory

Hydrochloric acid Solution Standardization

• Accurately weigh about 0.5 g of THAM (Tris (hydroxymethyl)-amino methane (tromethamine), previously dried at 105° for 3 hours and cooled in a desiccator, transfer to a conical flask.
• Dissolve in 50 ml of distilled water.
• Add 2 drops of Bromocresol Green indicator.
• Titrate with 0.1M Hydrochloric acid to a pale yellow endpoint.
• Each 121.14 mg of tromethamine is equivalent to 1 ml of 0.1M hydrochloric acid.
• Calculate the molarity by the following formula:

           THAM in mg
M = ---------------------
        121.14 x HCl in ml