Notes
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:
- 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.
- Close the balance door/lid to avoid drafts
from air currents that will cause readings to
fluctuate.
- 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.
- 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.
- Clean up any spills immediately using a brush.
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Figure 2.1: Electronic Laboratory
Balance