Last Update 30/ 06/ 2000
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TITRATION: Experimental practice of quantitative volumetric analysis. The objective of the titration is the determination of the concentration or the mass of the minimum formula from the titrated chemical material composing a pure liquid or a solution. The titrant chemical material, composing another liquid or solution is used to meet the objective above, by means of a chemical reaction that will present at least one observable change. Generally the burette is filled with the titrant, while the titrate is in the conical flask. Next, the titrant is added by carefully opening the stopcock on the burette. The mixture is stirred to keep it as homogeneous as possible. The chemical reaction of the titrate with the titratant enables the titration. On every titrant addition, the reaction consumes part of the titrate. If all the titrate is consumed by the last titrant addition, the equivalence point is reached. It is very easy to reach the equivalence point with the simulator, but not so easy in the experiment with the chemical reagents. Experimentally approximations are acceptable, they depend on the precision of the analytical balance used to prepare the solutions, on the precision of the volumetric vessels and on the stability of the temperature on the surroundings. Best result quality is achieved when the chemical energies of attraction between the titrate component and titrant forming the reaction product are high and when the chemical energies of attraction between titrate and solvent and titrant and solvent will not compete to revert the product into the reagents. Additionally impurities in the materials and in the environment, particulate in suspension in the air, liquid evaporation, the chemical stability of the components, reaction speed and the operator's technical performance play a role on the result quality. Opening the simulator stopcock with the cursor by a push and drag mouse action counter clockwise, ten different micro litres values of NaOH 0.1 mole L-1 are liberated over 50 mL of HCl on each vertical mouse pulse displacement. Horizontal displacements liberate equal microliters quantities of NaOH.
To restart the experiment, click on the repeat button (after washing electronically the vessels).
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