Final answer:
Calibrating a micropipette with oleic acid rather than water is important because oleic acid's lack of strong interaction with glass surfaces results in a convex meniscus, enabling more precise calibrations and consistent volume measurements.
Step-by-step explanation:
Calibrating a micropipette with oleic acid solution instead of water is necessary due to the interaction between the liquid and the glass of the pipette. Oleic acid does not form strong interactions with the polar Si-OH groups on the glass surface, resulting in a convex meniscus within the capillary of the micropipette.
Water, being highly polar, will adhere to the glass and form a concave meniscus, which can lead to inaccurate volume readings due to the different meniscus shape. Oleic acid, with its convex meniscus, minimizes the discrepancy caused by adhesion and ensures more precise calibrations and consistent volumetric measurements when using the micropipette for its intended application.
Therefore, calibrating with oleic acid is advantageous, as it better represents the behavior of non-polar or less polar substances typically handled with a micropipette in a laboratory setting.