Cleaning Glassware for Volumetric Measurements

Clean glassware is critical to achieving reliable results in the laboratory. For

volumetric measuring devices you are using, it is best to clean them with water

first and then to clean with the liquid that you will be using. The primary idea is

that a little bit of the liquid always gets left behind on surfaces, so the best thing

to do is ensure that the liquid left behind is the liquid you are using in the

measurement.

When rinsing glassware for cleaning, you should do multiple small volume

cleanings instead of one large volume cleaning. Rinsing a beaker three different

times with 10 mL of water each time is much more effective than rinsing once

with 30 mL of water. When rinsing make sure to coat all of the walls of the

glassware with the rinse liquid.

Volume Measuring Devices

Below are descriptions of some of the

common tools in the chemistry

laboratory for measuring volumes and

tips and tricks for using them.

Beakers and Erlenmeyer Flasks

Beakers and Erlenmeyer flasks are

convenient ways to work with liquids in

the laboratory because it is easy to add

and remove liquids to them. Beakers and

Erlenmeyer flasks come in many

different sizes (total volumes) and often

have markings along the side that

indicate additional volumes. For

example, a 100 mL beaker might have

markings every 10 mL and a main

marking at 100 mL.

It is tempting to use beakers and

Erlenmeyer flasks to measure a volume

because they are always readily

available, but the markings on these

tools are like the picture below, a “mL

inspired volume.”

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Figure 3.2: Erlenmeyer Flask: "Erlenmeyer Flasks

1" by biologycorner is licensed under CC BY-NC

2.0.

Figure 3.3: Beaker: "Siphon beaker"

by niallkennedy is licensed under CC BY-NC 2.0.