Burette, what is it, price and how to choose it?

November 2, 2021

burette is a laboratory material that consists of a graduated glass with a tap at one end, which serves to deposit counted volumes of a liquid. This tool consists of a long, graduated glass with a stopcock at the lower end of the conical tube. What is the outlet of the stopcock. The liquid is controlled thanks to the flow that goes from the tip to the stop valve.

There are two known types of buret: the volumetric buret and the digital buret. It is known as a volumetric burette to one that delivers volumes measured in liquid. On the other hand, burettes with syringes, but with a precision hole, are known as piston burettes. These can usually be operated manually. Finally, a weight buret is one in which the measure that provides weights is in liquid.

The liquid burette is that instrument in which the stopcock is located at the bottom. And, while the precise volume of the dispensed liquid is determined by reading the graduations marked on the glass tube. On the other hand, in the gas burette, the stopcock is at the top. Unlike the liquid instrument we mentioned earlier.

The buret tube is filled with a liquid, such as water, oil, or mercury, and the bottom of the tube is attached to a reservoir for the liquid. Gas is collected by displacing the fluid in the burette, and the amount of gas is measured by the volume of fluid displaced.

Next, we will talk in detail about one of the very important laboratory materials, such as the Büchner Funnel . Join us!

What is a burette?

A burette is a laboratory equipment commonly used to carry out a titration. A titration is a technique in which a solution of a known concentration is used to determine the unknown concentration of a second solution. A visual indicator generally indicates the completion or end point of the experiment.

The glass version is relatively low-cost equipment often used in school and university laboratories. It is used to perform titrations to deliver measured volumes of a solution of known concentration.

It is generally available in the form of a long, graduated glass tube with a tap and stopcock at its lower end, and a tapered capillary tube at the outlet of the stopcock. The stopcock valve controls the flow from the tube to the tip of the burette.

Burette overview

A burette is a volumetric measuring glass used in analytical chemistry for the precise dispensing of a liquid, especially one of the reagents in a titration. The buret tube has graduated markings from which the dispensed volume of the liquid can be determined.

Compared to a volumetric pipette, a burette has similar precision when used at full capacity, but since it is generally used to deliver less than its full capacity, a burette is slightly less accurate than a pipette. The burette is traditionally used to measure the volume of a substance in dispensed form, but it differs from a measuring cylinder in that its graduations measure from top to bottom.

The difference between the initial measured volume and the final volume is equal to the amount dispensed into the buret tube. The precision and control that the burette gives over other means of adding solution are helpful for use in titration.

History of the burette

The first burette was invented in 1845 by the French chemist Étienne Ossian Henry . In 1855, the German chemist Karl Friedrich Mohr introduced an improved version of Henry’s burette, with graduations inscribed on the burette tube. The word was coined in 1824 by the French chemist Joseph Louis Gay-Lussac.

What the burette measures

The volume markings, also called graduations, on a burette start at zero at the top and increase to the bottom. A laboratory tool can normally hold up to 50.00 milliliters of liquid. Other larger or smaller burettes will vary according to their use. The volume markings must be accurately placed in 0.1 mL increments. This is so that the burette can read the volume down to the first decimal place and then estimate the second decimal place.

The fluid takes a curved shape called a meniscus. If you want to learn to master this lab, it is important to read the lower part of the meniscus . The accuracy of this instrument is usually at the top.

The truth is that if you use a single reading you will not have many results. However, if you carry out a certain group of tests, in which you pour considerable amounts of liquid, you can have a better appreciation of the reading. Everything is a matter of practice and training. Nothing more.

How to use the burette

The burettes are used for titration and are calibrated to give a correct measurement. First rinse  very well with the solution that you will use for the titration. Then fill the burette slightly higher than the zero mark. To activate the stopcock, drain the solution but never below the capacity of the zero mark. Note that no air bubbles will remain inside the burette. Fill more titration solution to a maximum of 10 mm above the zero mark and be careful not to wet the buret wall above the liquid level.

When reading the meniscus at eye level, drain the solution to the exact zero level. In this step, you need to clean the drops on the tip. Then you need to open the stopcock very slowly and start the titration and also pay attention not to touch the tip with the wall of the container you use. When the color changes, stop the titration process and wait 30 seconds for the timeout.

Types of burette

volumetric burette

volumetric burette can be made of glass or plastic, which has a straight tube and a graduation scale. At the tip of the burette, there is a stopcock and a valve designed to control the flow of the solution that is poured into it. The barrel of the stopcock can be made of glass and even plastic.

These burettes must be lubricated with some characteristic elements, either petroleum jelly or a grease sold specifically for that use. It is important to note that they are manufactured in order to provide specific tolerances, which are designated class A or B, engraved on the glass.

The amount of solution added to the base should be read correctly, always looking directly at the bottom of the meniscus. This is the case with most solutions. In view of getting a correct reading. It is important to note that, before reading the data in a buret, the bubbles must be removed or the results will not be correct.

The product specification or specification is used as the identification of the volumetric burette, for example, nominal volume, unit volume, limit of error, precision class, and manufacturing related details. The specification is a direct association with the use of each laboratory equipment.

Bureta digital

digital burette is relatively high-cost equipment with more sophisticated features than glass. It can be connected to a computer and your titration readings can be saved to it. In digital burettes, a high precision piston is used to deliver aliquots. They have a glass barrel and their piston is made of glass. They should be used according to the nature of the solution to be assessed; whether or not it has a corrosive effect on glass.

The barrel is held in a fixed position and the plunger moves gradually, either by turning the wheel by hand or by a stepper motor. The volume is displayed on a digital display. A high precision syringe can be used to deliver very precise aliquots. Digital burettes feature the ability to be controlled by a computer without the need for the employer to touch it. For example, a titration can be digitally recorded and then numerically processed. This to find the end point.

Electronic burette

An electronic burette is designed with ergonomics and intuitive handling in mind. It offers sophisticated features and functionality, such as motor-controlled piston movement, a touchscreen control panel with graphical user interface, and calibrated preset speeds for highly accurate titrations.

Its motor-controlled piston movement eliminates the limitations of digital burettes and glass burettes that are manually dispensed. The easy-to-use touch screen guides quick and accurate titrations and displays numerical data down to the second decimal place.

It also offers the user the option of working at preset speeds during titrations, including drop-by-drop dispensing, helping to achieve the end point with high precision.

Dr. Loony Davis5
 | Website

Born and raised in Brussels in an English family, I have always lived in a multicultural environment. After several work experiences in marketing and communication, I came to Smart Water Magazine, which I describe as the most exciting challenge of my career.
I am a person with great restlessness and curiosity to learn, discover what I do not know, as well as reinvent myself daily, someone who is curious about life and wants to know. I enjoy sharing knowledge.
This is my personal project but I also collaborate in other blogs, it is the case, the most important web on water currently exists in the US, if you are interested you can read my articles here.

Leave a Reply

Your email address will not be published. Required fields are marked *