Question
Before the first titration , the 25cm^3 pipette is rinsed with a small volume of the 0.100 mol dm^-3 barium hydroxide solution. State why it is good practice to rinse the pipette in this way.
Answer
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Edwin
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Answer
It is good practice to rinse the pipette with the solution to be used because it ensures the accuracy of the volume measurement.
Explanation
In a chemistry experiment, the rinsing process is important because residues from previous solutions in the pipette could potentially dilute or contaminate the solution of interest. In this case, remnants of water or other solutions left in the pipette could alter the concentration of the barium hydroxide solution.Moreover, lingering droplets of water or other solutions would effectively dilute the 0.100 mol/dm³ barium hydroxide solution if it were introduced into the pipette without rinsing. Rinsing the pipette ensures that exactly 25 cm³ of the intended barium hydroxide solution at the anticipated concentration are measured, preserving the accuracy of the experiment. It is routine best practice to always rinse the pipette with the solution to be used to curtail any form of erroneous outcome as much as possible. This level of attention to detail unlocks reliability and high degree of accuracy when undertaking experiments.