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How to read the burette

The purpose of burette reading is to tell you how much solution has been dispensed, instead of telling you how much the burette contains. Unlike other volumetric glassware, the zero scale on a burette is written on top. Measurement scale on the burette is at 0.10 intervals. All burette readings are given to an accuracy of 0.05 mL.

  • Make sure your eye is at the same level of the meniscus to avoid an error. For water and most liquids, the meniscus is concave or like a U shape. Read the center of the meniscus or the bottom of the U-shape.

A zoomed-in section of the burette between 20.5 milliliters and 18.5 milliliters shows the level of the solution in the burette. There is a concave meniscus at the surface of the solution. There are 3 eyes on the right side of the burette looking at the level of the solution from above, at, and below the meniscus. The eye above the meniscus reads the solution level to be at 19.42 milliliters. The eye at the same level as the meniscus reads the level of the solution to be 19.5 milliliters. The eye below the meniscus reads the level of the solution to be 19.62 milliliters. The correct measurement of the solution level is 19.5 millimeters.

Figure: How to read the meniscus. The correct reading is 19.50 mL. Due to parallax error, the reading can be 19.62 mL or 19.42 mL.

  • The first and final reading of the burette should be recorded. The difference between the first and final reading is called the titer.
  • Readings should be recorded to the nearest 0.05 mL. Examples of readings: 22.05, 23.00, and 23.05 mL.

Referred from:

Article
Titration apparatus