Separating Substances, Measuring Mass, and

Analyzing Data - Technique Laboratory

Introduction for Measurement of Masses

Balances are used to measure masses of objects. Chemists have used balances

for centuries to gain key insights into chemical processes and reactions. The

balance has long been one of the most important tools in the chemistry

laboratory!

Use of Balance

The tare button is the one important button on

the balance. By pressing the tare button you

“zero” the balance. Zeroing the balance means

that whatever mass is currently on top of the

balance is set to zero mass.

Tips for measuring masses using a top-loading

balance:

1. Never put the object being massed directly

on the balance. Always use a piece of

weighing paper or a container (beaker/flask)

to hold the material being massed.

2. Close the balance door/lid to avoid drafts

from air currents that will cause readings to

fluctuate.

3. All objects being massed must be at room temperature. This avoids buoyancy

correction problems due to warm air being less dense than cold air and

prevents air currents that will cause readings to fluctuate.

4. Write down all the digits from the balance. If you are asked to mass 2 grams

of material, it is perfectly fine if the balance reads 1.956 grams, but you must

write down the actual value (1.956 grams) and not just write 2 grams in your

laboratory notebook.

5. Clean up any spills immediately using a brush.

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Figure 2.1: Electronic Laboratory

Balance