Summary
Highlights
When measuring the volume of a liquid, always get down to eye level with the liquid to avoid inaccurate readings. Observe the meniscus and always read the measurement at the bottom of the curve. For example, if the bottom of the meniscus is at the 75 ml mark, that is the accurate measurement, even if the top of the curve reaches 76 ml. Looking from above or below eye level can lead to parallax errors.
To accurately find volume, graduated cylinders are used instead of beakers due to their precision. When water is poured into a graduated cylinder, it forms a curve called a meniscus. It is crucial to measure volume at the bottom of this curve, not the top, as water clings to the edges of the cylinder forming this curve. If using a glass graduated cylinder, the yellow plastic piece at the top is for protection against breakage, not measurement.
To precisely adjust the volume of a liquid, such as increasing it from 75 ml to 77 ml, use a pipet (dropper). Hold the pipet over the graduated cylinder and carefully add drops until the bottom of the meniscus reaches the desired mark. If too much liquid is present, it's best to dump some out and then add liquid back with the pipet rather than trying to remove liquid directly with the pipet, as this can alter the measurement.