Preparation and Standardisation of Solutions Using Titration

Section 1: Understanding Titration

Titration: A quantitative laboratory method used to determine the concentration of an unknown solution (analyte) by reacting it with a standard solution (titrant).
Burettes: Precision instruments used in titration to measure out the titrant. They can discharge liquid in tiny, precise amounts.
Indicators: Substances that change colour at the end point of a titration. They are chosen depending on the reaction type and pH change.

Section 2: Preparing a Standard Solution

Standard Solution: A solution of known concentration, often used as the titrant. It’s prepared by dissolving a calculated amount of solute in a known volume of solvent.
Calculating moles: Use formula Mass = Moles x Molar mass, and rearrange to find the amount needed. Always verify calculations before proceeding.
Dissolving the Solute: Add the calculated amount of solute to a beaker and dissolve in distilled water.
Transfer to Volumetric Flask: Use a wash bottle and funnel to carefully transfer the solution, ensuring all solute is included. Top up to the mark with distilled water. Shake the flask gently to mix.

Section 3: Performing a Titration

Pipetting: Fill a pipette with the analyte and dispense it into a clean conical flask.
Adding Indicator: Add a few drops of an appropriate indicator to the conical flask.
Running the Titration: Fill the burette with the standard solution, noting the initial volume. Then gradually add the titrant to the flask, swirling to mix, until the end point (colour change) is achieved.
Measuring Volume: Record the final volume of titrant in the burette. The difference between initial and final volumes is the amount used in the reaction.

Section 4: Analysing Titration Results

Average Titre: Repeat the titration several times (replicates) to ensure accuracy. Calculate the average volume of titrant used (disregard any anomolous results).
Calculating Concentration of Analyte: Use formula Concentration = Moles ÷ Volume. Remember that the volume should be in dm³, so convert mL to dm³ by dividing by 1000.
Potential Errors: Possible errors include measurement inaccuracies, misjudging the end point, or not fully transferring solutions. Always use careful technique, and perform multiple replicates to minimise these errors.

Section 5: Safety and Disposal in Titration

Safety: Always wear protective equipment (glasses, coats, gloves) to guard against spills. Handle glassware, especially burettes, with care.
Disposal: After titration, dispose of solutions as per lab safety guidelines. Wash and rinse all glassware ready for next use.