Burettes

About

What is a burette? If you are a chemical scientist or happen to know one, it’s likely that you have heard the term ‘burette’ being used. If you have ever wondered, what is a burette and what is a burette used for, let’s help you solve this mystery. For one who has ever performed a quantitative analysis in a chemistry lab, you would most likely have come across a burette. The word ‘burette’ has French origins and was coined by the chemist, Joseph Louis Gay-Lussac. A burette is a laboratory apparatus, which consists of a long, graduated glass tube, with a stopcock on its lower end. It is used in quantitative chemical analysis to measure the volume of a liquid or gas. It is used to dispense and measure a variable amount of a chemical solution. The stopcock valve controls the flow of the fluid from the burette, either in a steady stream or drops by drop. A burette (sometimes also spelt as buret) is often used in the process of titration. Titration is a process of chemical analysis in which the quantity of some constituent of a sample is determined by adding to the measured sample an exactly known quantity of another substance with which the desired constituent reacts in a precise proportion. Types of burettes Burettes can be classified in different ways: As per the mechanism 1) Volumetric burette – The volume scale is printed on the burette wall 2) Piston burette – Syringe design with barrel and plunger arrangement As per operation 1) Manual burette – Marked by graduations and operated manually 2) Digital burette – Operated manually or electronically with digital displays 3) Electronic burette – Motor-controlled operations with the elimination of human errors, and electronic display As per fluid handled 1) Liquid burette – Dispenses liquids. The stopcock is at the bottom of the burette, and the flow of the fluid is enabled by gravity 2) Gas burette – Dispenses gases. The stopcock is at the top of the burette, and the gas is collected by displacing a liquid like water or