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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: sidoniaknight on September 06, 2019, 10:46:16 PM

Title: What is the precision of a scale, pipet, and Buret?
Post by: sidoniaknight on September 06, 2019, 10:46:16 PM

Lab question asks what the precision of the scale. The scale reports out like this: 56.231g.

So I would say this scale is precise to 0.001 g correct? I ask because I've read about some uncertainty being reported as ±.0005 g .

Furthermore, if a buret's graduations are .1 mL increments, I would report my measurements to an extra decimal place out. Ex: 2.45mL

However, am I correct in assuming that the buret's precision is within 0.1 mL? Thanks for the help. My textbook isn't exactly helping.

Title: Re: What is the precision of a scale, pipet, and Buret?
Post by: jeffmoonchop on September 09, 2019, 12:30:52 PM

The burette should say on the side what the error is. If the increments are 0.1ml apart it would be difficult to report to 3dp. I know at school teachers will tell you to report to 2dp even though this method relies entirely on human judgement of where the meniscus is.

Title: Re: What is the precision of a scale, pipet, and Buret?
Post by: Borek on September 09, 2019, 05:27:39 PM

Depends on the glassware class, see discussion here:

http://www.titrations.info/pipette-burette