Final answer:
Blow-out pipettes require the last drop to be blown out for accuracy, whereas Mohr pipettes do not extend calibration to the tip and allow the last drop to remain.
Step-by-step explanation:
The blow-out pipettes, also known as serological pipettes, are designed to measure volumes of liquid with a high degree of accuracy. After the liquid is dispensed, the remaining droplet at the tip of these pipettes must be blown out to ensure delivery of the full measured volume. On the other hand, Mohr pipettes, a type of graduated pipette, are designed to deliver measured volumes without the need to blow out the last drop. The calibration marks on a Mohr pipette do not extend to the tip, and the liquid is expelled by gravity only.Blow-out pipettes are often used in procedures needing full volume delivery, such as in quantitative chemical analysis or when preparing solutions. Mohr pipettes are more suitable for applications where the final drop can safely remain in the tip, for instance, in qualitative analysis. It’s important to choose the appropriate type of pipette based on the accuracy requirements and nature of the experiment.