Volumetric Analysis · 6 min read
Titration apparatus and procedure
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Introduction to Titration
Volumetric analysis is a way we find the unknown concentration of a solution by reacting it with one we already know. The most common method is titration. Think of it like a market scale: you keep adding weight until both sides balance perfectly.
It is a laboratory method used to measure exactly how much acid reacts with a base.
Essential Lab Tools
To do a titration, you need specific equipment. If you use a dirty tool, your result will be wrong, just like how a small stone in your garri spoils the meal. The main tools are:
Burette: A long glass tube with a tap at the bottom used to measure the volume of the acid used.
Pipette: A thin glass tube used to suck up and deliver a fixed volume of the base, usually 20 cm3 or 25 cm3.
Conical Flask: The 'mixing bowl' where the acid and base react.
Retort Stand: The heavy iron stand that holds the burette straight so it doesn't fall like a weak fence.
White Tile: Placed under the flask so you can see the color change clearly, just like how you see dirt better on a white shirt.
Cleaning the Apparatus
Before you start, you must wash your tools. Wash everything first with clean water and then with detergent. But here is the secret for a perfect result: rinse the pipette with the base and the burette with the acid.
Rinsing ensures that leftover water drops do not make your chemical weaker than it should be.
The Titration Procedure
1. Use a pipette to measure a fixed volume of the base into a clean conical flask.
2. Add two or three drops of a suitable indicator to the base in the flask.
3. Fill the burette with acid up to the 0.00 cm3 mark, ensuring there are no air bubbles in the tip.
4. Slowly add the acid from the burette into the flask while swirling the flask gently.
5. Stop immediately when the color changes permanently. This is the End point.
6. Read the final volume on the burette and record it in your table. Repeat until you get two or three readings that are very close (concordant).
How to Read the Scale
When reading the burette or pipette, your eyes must be at the same level as the liquid. Always read the bottom of the curved surface of the liquid, which we call the Meniscus.
Always read the lower part of this curve to get the correct measurement.
Key points
- •Wash all apparatus with water, then rinse the burette and pipette with their respective chemicals.
- •The pipette measures the base, while the burette measures the acid.
- •The conical flask should only be rinsed with distilled water, never the base.
- •Remove the funnel from the burette before taking your reading.
- •The end point is reached when the indicator changes color permanently.