In a rigorous discipline like chemistry, accuracy and precision are important. Accuracy indicates how close a measurement is to its true value. Inaccurate weights can lead to inaccurate results that are not too close to the truth. Therefore, it is very important to learn to correctly weigh the mass of an object.
This section contains:
Video instructions
Quick instructions
Questions to test you've understood how to do the technique properly.
Here is a video for us to learn how to use a balance to weigh materials.
This video give you lots of detail on how to do the technique correctly.
Place the weighing bottle on the top-loading balance and add the approximate mass of the desired sample to the bottle. Close the lid to avoid sample contamination.
The analytical balance is turned on and zeroed and placed in the weighing bottle containing the sample. Record the weight x. (Close the glass door of the analytical balance when it is heavy)
Pour the sample into the flask to be used.
After zeroing, place the empty weighing bottle with the sample residue into the analytical balance and weigh it. record weight Y。
Then the weight of the sample in the beaker can be obtained as X-Y
Questions to test you've understood how to do the technique properly.
Is it necessary to close the glass door when using the electronic balance? Why?
Volatile and corrosive items need to be weighed in airtight containers, why?
Can the electronic balance be moved after calibration?
It is necessary to close the glass door when using the electronic balance. Closing the glass doors on both sides can reduce the influence of the external environment on the reading, such as wind, dust, etc.
Volatile and corrosive items are corrosive and will damage the electronic balance if not kept in an airtight container.
No. The electronic analytical balance is a high-precision electronic balance with an accuracy of 0.1 mg. Not only the position movement, but also the magnetic field change and the environmental temperature change will affect the accuracy of the measurement.