Preparing a dilution
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Water is not always the best solvent for preparing a solution! Be sure to choose the right solvent!
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Side note: this video was made to emphasize the important practical aspects, while at the same time keeping it humorous.
Introducing a solution with a graduated pipette
The volume introduced must correspond to the nominal volume of the pipette
![illustration of a pipette in a flask. the pipette does not touch the wall of the flask.](/resources/images/fiches/bases/solution-dilution/solution-img-1.png)
No contact between the pipette and the side of the flask.
No capillary action for the last drops
The poured volume is not correct
![illustration of a pipette in a slanted vial. the tip of the pipette makes contact with the wall of the vial.](/resources/images/fiches/bases/solution-dilution/solution-img-2.png)
Contact between the pipette and the side of the flask.
Suction of the last drops by capillary action
The poured volume is correct
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Never withdraw the stock solution directly (solution of known concentration or commercial solution) from its container. It is imperative to use an intermediate container.
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