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IMAGE. Equipment typically used when preparing a solution in a volumetric flask includes the volumetric flask and its glass stopper, a medicine dropper, and a funnel. Water can be delivered from the beaker or wash bottle.
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A volumetric flask is used to measure very precisely one specific volume of liquid (100 mL, 250 mL, etc., depending on which flask you use). This flask is used to accurately prepare a solution of known concentration.
The etched mark on the neck of the volumetric flask has been calibrated by the manufacturer, but if very accurate solutions are needed the volumetric flask must be manually calibrated (by determining the mass of a solution of known density and calculating the volume).
NEVER store solutions in a volumetric flask.
AVOID pipetting directly from a volumetric flask.
Why do you think a medicine dropper is used when preparing solutions in a volumetric flask?
Answer
Since volumetric flasks are used to prepare solutions of very specific volumes, the quantity of liquid added to the flask must be
carefully controlled. A medicine dropper allows you to add liquid in small volumes, which helps ensure that you add the correct quantity of liquid to the flask.
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