Titrations
11
Titrations The Proper Use Of A Buret
description
Titrations. The Proper Use Of A Buret. Obtain a buret clamp. Open the clamps and insert the buret. Position the buret assembly over the center of the hotplate. Attach the buret clamp to ring stand. Assemble the Ring Stand and Buret Clamp. Make sure the valve is OFF!. - PowerPoint PPT Presentation
Transcript of Titrations
TitrationsThe Proper Use Of A Buret
Assemble the Ring Stand and Buret Clamp
Attach the buret clamp to ring stand.
Obtain a buret clamp.
Open the clamps and insert the
buret.Position the buret assembly over the
center of the hotplate.
Fill the Buret (NaOH)
Make sure the valve is OFF!
Place CLEAN funnel in top of buret.
Carefully add the titrant.
Go Slow!
Don’t overfill!
Remove funnel when finished.
Drain The Buret
Open the valve....
...and let a small amount of liquid run into a waste beaker.
Inspect the buret tip for bubbles.
Drain the buret again to eliminate bubbles.
Ready to go!No bubbles in tip.
Record Initial Volume
2.00 mL
3.00 mL
2.68 mL
2.50 mL
2.60 mL
2.70 mL
ALL BURET MEASUREMENTS MUST INCLUDE 2 DECIMAL DIGITS!!!!
Add Liquid to Flask
Carefully pour liquid into flask.
Add the stir bar.Don’t splash!
Add the indicator.
Stir and Titrate
Flask in center of hotplate.
Stir (2 or 3) HEAT TURNED OFF!
Faint color change that quickly vanishes.
Close to the Endpoint?Add only a little!
Partial drop clings to buret tip.
Use distilled H2O to rinse drop into flask.
Don’t miss!
The End of the Titration:Endpoint
Faint persistent color change....just right!
Too dark...you’ve gone too far!
Final Reading
14.00 mL
13.00 mL
13.88 mL
13.50 mL
13.80 mL
13.90 mL
ALL BURET MEASUREMENTS MUST INCLUDE 2 DECIMAL DIGITS!!!!
Calculate the dispensed volume.
2.68 mL
13.88 mL
11.20 mL 11.2 mL
Vfinal
Vinitial
-
2 Decimal Digits!!
