Titrimetric analysis commonly referred to as volumetric analysis offers distinct advantages over cumbersome gravimetric methods:
- Speed of analysis
- Instantaneous completion of reactions
- Greater accuracy due to minimization of material loss involved in decanting, filtration, precipitation or similar operations
- No cumbersome and time consuming heating on open flames or hot air oven drying is necessary
- Instantaneous monitoring of endpoints through indicators or electrometric methods.
It is essential to observe precautions to take complete advantage offered by titrimetric methods of analysis . Some useful tips for improving accuracy and precision of your titrimetric analysis results are suggested in this article:
- Glassware for preparing volumetric solutions should be clean and dry
- Use calibrated volumetric apparatus
- Do not dry volumetric glassware with the stopper affixed and at temperatures exceeding 60°C
- Keep the delivery knob of the burette well lubricated for freedom of movement but excessive grease should be avoided as it can block the delivery hole
- Pipette used should be rinsed 1-2 times before transferring the reagent
- There should be no liquid drops sticking outside the burette or pipette tips. Always wipe using lint – free tissue.
- Avoid parallax error by noting burette readings at same eye level as level of meniscus inside the burette
- Always take readings at lower meniscus level for transparent liquids and at upper t level for opaque or coloured liquids. It is helpful to keep a white paper behind the meniscus level for improved accuracy of measurements.
- Nearing and point fine control reagent delivery drop wise
- Ensure free movement of nozzle tap before starting the titration as a stuck nozzle can prove to be a disaster. It can lead to uncontrolled flow of reagent or in extreme cases even breakage of knob in your hand.
- Place the titration flask on a clean white tile to detect minute colour changes and remember to keep it mildly agitated to ensure instantaneous homogeneity of reaction mixture. Vigorous shaking should be avoided as it can lead to splashing.
Titrimetric methods are being slowly replaced by instrumental techniques but are popular to this day in school/ college and industrial laboratories due to their affordability and easy comprehension by the chemist.