Chemical Forums

Specialty Chemistry Forums => Other Sciences Question Forum => Topic started by: Dhisbdj on October 29, 2020, 04:56:50 PM

Title: Question about glassware measurements.
Post by: Dhisbdj on October 29, 2020, 04:56:50 PM

Why do different glassware give different measurements when measuring the same amount ? I measured 15 ml on volumetric flask but got less using graduated cylinder.

Title: Re: Question about glassware measurements.
Post by: Borek on October 29, 2020, 08:23:40 PM

A lot depends on the glass accuracy and technique used. Not knowing what and how you did, it is impossible to comment.

Title: Re: Question about glassware measurements.
Post by: jeffmoonchop on October 30, 2020, 12:46:53 PM

Cylinders shouldn't be used if accuracy is needed. Volumetrics are more accurate. But you can buy different grades of glassware, Ideally the volumetric should be A rated. And make sure your meniscus is sitting on the line.

Title: Re: Question about glassware measurements.
Post by: jeffmoonchop on October 30, 2020, 12:47:48 PM

Also if you pour the liquid from the volumetric into the cylinder, you'll leave some behind and get less in the cylinder.