Illustrated Guide to Home Chemistry Experiments

(Amelia) #1
Chapter 3: Equipping a Home Chemistry Laboratory 23

FIGURE 3-14: 10 mL and 100 mL graduated cylinders

ISvRSUSo E U.S. LABELING
Volumetric glassware made in the United States often uses
the traditional TC and TD markings. Other than products
intended for export to the United States, most volumetric
glassware made in Europe and Asia uses the ISO-standard
labeling of “IN” for To Contain and “EX” for To Deliver.

EvRHINGE yT yoU ALwAyS wANTEd To kNow

Volumetric Glassware .......................................................................................................................


One of our readers, Michael Dugan, has written an
excellent introduction to volumetric glassware.
To learn more about this subject, visit Mike’s website at
http://tinyurl.com/egkj8.

Burette volumetric flask
Nominal volumeClass A Class B Class A Class B
1 mLn/a n/a n/a n/a
5 mLn/a n/a n/a n/a
10 mL ±0.02 mL ±0.04 mL ±0.02 mL ±0.04 mL

25 mL ±0.03 mL ±0.06 mL ±0.03 mL ±0.06 mL
50 mL ±0.05 mL ±0.10 mL ±0.05 mL ±0.10 mL
100 mL ±0.10 mL ±0.20 mL ±0.08 mL ±0.16 mL
250 mLn/a n/a ±0.12 mL ±0.24 mL
500 mLn/a n/a ±0.20 mL ±0.40 mL

1000 mLn/a n/a ±0.30 mL ±0.60 mL
2000 mLn/a n/a ±0.50 mL ±1.00 mL

TABLE 3-1: Comparison of Class A and Class B tolerances for volumetric glassware TABLE 3-1 (continued): Comparison of Class A and Class B tolerances for volumetric glassware


use a graduated cylinder to measure liquids with moderate to
moderately high accuracy—from ±1% to ±0.2% of full capacity,
depending on the capacity and quality of the cylinder. Graduated
cylinders are made in glass and various plastics. Although they
are breakable and usually more expensive than similar plastic
models, I prefer glass cylinders because they are much more
resistant to organic solvents, oxidizers, and other chemicals, and
because they are much easier to keep clean. Figure 3-14 shows
typical 10 mL and 100 mL glass graduated cylinders.

Single-scale graduated cylinders are graduated from zero
at the bottom of the cylinder to the nominal capacity near
the top. Double-scale graduated cylinders have a second set
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