Question

A 1.75 mL sample is needed for an experiment. Both a 2- and a 5-ml pipet will measure this amount. Which pipette is best to use and why?

A. The 2-ml pipette is best because it's more accurate.
B. The 5-ml pipette is best because it can hold more.
C. The 2-ml pipette is best because it can measure smaller volumes.
D. The 5-ml pipette is best because it's easier to use."

Answer 1

The correct option is A). The 2-ml pipette is the best choice for measuring a 1.75 mL sample because it provides better accuracy and precision for smaller volumes, which is important for laboratory measurements.

Step-by-step explanation:

To answer which pipette is best to use for measuring a 1.75 mL sample, one must consider the accuracy and precision needed for the experiment. The closer the maximum capacity of the pipette to the desired volume, the more accurate and precise the measurement is likely to be. Hence, the 2-ml pipette is best because it is closer to the desired volume and is likely more accurate for measuring volumes that are close to its maximum capacity. It can measure smaller volumes more reliably than the 5-ml pipette, which can introduce more room for error due to its larger scale.

Pipettes are a type of volumetric glassware and are designed to deliver a known volume accurately. In general, smaller-volume pipettes provide better accuracy and precision for smaller volumes because the graduations are closer together, allowing for a finer resolution in measurement. This is important when performing measurements in a laboratory setting where precision and accuracy are critical.