Video Transcript
Why is a volumetric pipet used to
measure out the known volume, aliquot, of a solution?
Let’s have a look at in what
situations a volumetric pipet would be used to answer this question.
One example of a common analytical
technique during which a volumetric pipet is often used is a titration. A titration is a precise procedure
that involves using a clamped buret to add a volume of solution into a conical flask
containing another solution. The solution of known identity and
concentration is often added to the buret. The known solution is used to
collect data regarding the other unknown solution, which in this example is
contained in the conical flask.
In order for this analysis to be
reliable, it is extremely important that the known solution be accurately
standardized and measured. Additionally, while we may not know
the identity or concentration of the unknown solution, it must be measured very
precisely so the titration data will be useful. For this reason, volumetric pipets
are often used when measuring substances for titrations.
A volumetric pipet has one single
gradation as it measures a single, specific quantity of liquid to a very high degree
of accuracy. A bulb is usually used to control
liquid entering and exiting the opening of the pipet when transferring and measuring
solutions. Though a volumetric pipet measures
only one fixed volume, it does so very accurately and is commonly used for
analytical techniques, such as titrations. Therefore, a volumetric pipet is
used to measure out the known volume, aliquot, of a solution to allow a very
accurate, fixed volume of a solution to be measured.
