Title: Measuring Volume and Mass
Course: BTEC-1100-301-302-303-F21 > Section: Module 1 - Calculations and Measurements

In a typical day as a biotechnician, you will make many measurements of volume and mass. You have already learned to use micropipettes to deliver small volumes of one to one thousand microliters. Larger volumes can be delivered using serological pipettes (typically 1 to 25 milliliters) or graduated cylinders (up to several liters). When you put liquid into either a serological pipette or graduated cylinder, the top of the liquid will form a U-shape. This U-shape is called the meniscus, and laboratory glassware is calibrated to be accurate at the bottom of the meniscus. See the photo below for an example.

To measure the volume of liquid in a graduated cylinder, you must mentally subdivide the distance between the 21 and 22 mL marks into tenths of a milliliter, and then make a reading (estimate) at the bottom of the meniscus. Image credit: Jack O’Grady, Austin Community College. OER Biotechnology eTextbook p. 56