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Acid-Base Titrations
Precautions!
1. Washing
Glassware
Washing Glassware
{Washing is a very critical step before titrations}
ALL glassware should be washed with tap water and
distilled water.
• Rinse your pipette with the sample you will titrate.
• Rinse your burette with the titrant.
• NEVER rinse your conical flask with the
sample!
2. Before
Titration
Fill the burette “directly” from the bottle of titrant (Not using a flask)
Use a funnel when filling the burette and make sure no solution is running on the
outside..
Burette
Look for air bubbles!
Remove by opening the tap to a vertical position until a continuous flow of titrant is obtained.
The pipette should also be free of air bubbles
Eye level..
Make sure you take an accurate reading from the burette by lowering (or raising) it to your eye level.
NB: Read the “bottom of the meniscus”
Burette
Remove the funnel before starting your
titration..
Place a piece of white paper under the flask during titration to see the end point clearly..
Don’t forget these!
3. During
Titration
Do not titrate while the burette is hanging far above the flask; every drop of titrant should fall inside the
sample!
Make sure you continuously swirl the flask with dropwise addition of the titrant…
Using both hands will help you avoid missing the exact endpoint..
Titration is done inside the sample NOT on the
walls..
Keep flask in the vertical position.
GOOD LUCK!
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