Question

If you are to measure 55 uL of a liquid for an experiment, which pipette should you use and what value should be displayed on its window?
Select one:
a. p20: 550
b. p200: 055
c. p20: 055
d. p200: 550
e. p1000: 055

Answer 1

Answer:

$\boxed{\text{b. P200; 055}}$

Explanation:

1. Type of pipette  

The three most common types of micropipette are shown in the table below.  

$\begin{array}{ll} \textbf{Type} &\textbf{V/ \mu L }\\ \text{P20} & 2 - 20 \\ \text{P200} & 20 - 200 \\ \text{P1000} & 200 - 1000 \\ \end{array}\\ \text{The only type that will dispense 55 µL is the \boxed{\textbf{P200}} }$

2. Window  

The window on a P200 micropipette shows three digits.  

The first digit is hundreds, the second is tens, and the third is units of microlitres.  

A measurement of 55 µL will display as 055.