| 0.1M Hydrochloric acid |
| 1.0 Scope: This procedure is applicable for preparation and standardization of 0.1M hydrochloric acid solution. 2.0 Apparatus: 2.1 1000ml volumetric flask 2.2 250 ml glass-stoppered, conical flask 2.3 100 ml graduated burette 2.4 100 ml volumetric flask 3.0 Reagents: 3.1 Hydrochloric acid AR grade 3.2 Anhydrous sodium carbonate AR grade 3.3 Methyl red solution 3.4 0.1M sodium hydroxide solution 3.5 Ethanol (95 %v/v) 4.0 Preparation of Reagents: Methyl red solution preparation : Dissolve 50.0 mg of methyl red in a mixture of 1.86 ml of 0.1M sodium hydroxide(NaOH) and 50 ml of ethanol (95 %v/v). After solution is effected, add sufficient purified water to produce 100.0 ml. 5.0 Preparation: Dilute 8.5 ml of hydrochloric acid with water to produce 1000 ml. To read this GTP Preparation and Standardization 0.1M Perchloric acid. 6.0 Standardization: Weigh accurately and transfer about 0.15 g or 150mg of anhydrous sodium carbonate(NA2CO3), previously heated at about 270°C for 1 hour to a 250 ml glass stoppered conical flask. Dissolved it in 100.0 ml of purified water and add 0.1 ml of methyl red soln. Add the 0.1 M HCL slowly from a burette, with constant stirring, until the soln. becomes faintly pink. Heat the soln. to boiling, cool and continue the titration until the faint pink colour is no longer affected by continued boiling. Each ml of 0.1M hydrochloric acid(HCl) is equivalent to 0.005299 g of Na2CO3. 7.0 Calculation: M* = Weight X 0.1 / V X 0.005299 8.0 Storage: Stored in a well fitted clear transparent glass bottle. |