An important error to avoid in volume measurement readings is parallax error.

This error occurs because the bottom of the meniscus is not in the exact same

location as the markings. The bottom of the meniscus is in the center of the

measuring device and the markings are on the walls of the device. You will get

an incorrect reading that has parallax error if your eye level is above or below the

meniscus. Always read volumes with your eye at the same height as the

meniscus to ensure you don’t have parallax error. This will often mean you need

to lift up the measuring device or reposition your body in order to be at eye level

with the meniscus.

Reminders for graduated cylinders:

1. Pay attention to carefully interpret the markings.

2. Avoid parallax error by having the meniscus at eye level.

3. Estimate the last digit to appropriately reflect the uncertainty of the

measurement.

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Figure 3.7: Parallax Example.png by JustinWick is licensed under CC BY-SA 3.0.