Burette

A burette (also spelled as buret)[1] is a graduated glass tube with a tap at one end, for delivering known volumes of a liquid, especially in titrations.

[3] A burette is a volumetric measuring glassware which is used in analytical chemistry for the accurate dispensing of a liquid, especially of one of the reagents in a titration.

[4] The burette tube carries graduated marks from which the dispensed volume of the liquid can be determined.

[6] A volumetric burette can be made of glass or plastic, and is a straight tube with a graduation scale.

Burettes are manufactured for specific tolerances, designated as class A or B and this also is etched on the glass.

In order to measure the amount of solution added in or drained out, the burette must be observed at eye level straight to the bottom of the meniscus.

With liquids that corrode glass, including solutions of alkali, the barrel and plunger may be made of polyethylene or another resistant plastic material.

The barrel is held in a fixed position and the plunger is moved incrementally either by turning wheel by hand, or by means of a step motor.