Bunsen burner
A Bunsen burner is a laboratory device designed to combine flammable gas, typically natural gas, with air before ignition, resulting in a controlled flame that is hotter than an unregulated flame. It consists of two main parts: a base and a tube, which features air holes for adjusting the air intake. The burner was introduced by German chemist Robert Bunsen in 1855, although its original design is attributed to Michael Faraday and later modified by Bunsen's assistant, Peter Desaga.
In operation, the gas and air mix optimally in a ratio of one part gas to three parts air, allowing for a clean and efficient burn. The flame produced has distinct characteristics, including a primary inner cone that is pale blue and a larger, colorless secondary flame. The highest temperature is found just above the primary flame, reaching around 2,700ºF (1,500ºC).
The Bunsen burner has influenced various applications, extending beyond laboratory use to home gas stoves and furnaces. Modern adaptations, such as Meker and Fisher burners, have improved efficiency and flame stability by utilizing metallic grids and forced air systems. The design and functionality of Bunsen burners continue to evolve, reflecting ongoing advancements in combustion technology.
On this Page
Bunsen burner
A Bunsen burner is a device used to combine a flammable gas with air before the gas is ignited. The device produces a flame that is hotter than it would be if the gas and air mixture were not controlled. The Bunsen burner, which is commonly used in laboratories, is named for German chemist Robert Bunsen. He introduced the burner in 1855 but did not design it. The original design was probably created by Michael Faraday and modified by Bunsen’s laboratory assistant, Peter Desaga. While most associated with scientific applications, the burner also made possible home gas stove burners and gas furnaces.
Gas burners were used by chemists for some decades before the Bunsen burner. However, they produced flames that were inconsistent and did not burn steadily. Degasa experimented with the design, changing the length and width of the tube. He eventually created a version that produced a flame that was colorless and did not produce soot.
Overview
The Bunsen burner has two parts, a base and a tube, also called a barrel or stack. The tube, which screws to the base, has air holes drilled in its bottom end. The bottom end of the tube has an inlet through which the flammable gas, usually natural gas, enters and mixes with air in the tube. The optimal ratio is about one part gas to three parts air. The gas and air mixture is ignited at the top of the tube. The combustion releases heat and light. The burner can be adapted for use with propane or butane cylinders should a natural gas source not be available.
The gas arrives at the burner through rubber tubing. The flow of gas may be regulated and the flame adjusted with a valve. A collar on the tube allows the amount of air to be adjusted by increasing and decreasing openings in the sides of the tube. Gas pressure forces the air and gas mixture to the top of the tube, where it can be ignited using a striker or long-nozzle lighter.
The flame consists of a primary flame, which is an inner cone that is small and pale blue. The larger, outer cone, called the secondary flame, is nearly colorless and is produced by excess gas combining with atmospheric air. The hottest part of the flame is just above the tip of the primary flame. It burns about 2,700ºF (1,500ºC).
Natural gas is mostly methane, which is a carbon-hydrogen compound. If the mixture contains too little air, it will not burn completely. Instead, heated carbon particles, or soot, will glow yellow, making the flame luminous. A mixture with too much air could burn inside the tube.
Just as Bunsen’s laboratory staff worked to improve the burners available to them, others have developed new variations of the Bunsen burner. Meker and Fisher burners use metallic grids to keep the flame at the top of the tube by increasing the turbulence of the gas and air mixture. The Fisher burner uses forced air. These improvements have increased the efficiency of the burners, so a secondary flame, which relies on surrounding air to burn the remaining gas, does not appear.
Bibliography
“Bunsen Burner Basics.” Flinn Scientific Inc., 2016, www.flinnsci.ca/api/library/Download/2b09de3ed1e147cbb2f0a12c0c2a15af. Accessed 16 Mar. 2023.
Brunning, Andy. "Today in Chemical History: Robert Bunsen and the Bunsen Burner." Compound Interest, 31 Mar. 2023, www.compoundchem.com/2023/03/31/bunsenburner/. Accessed 13 Nov. 2024.
Dharavath, Arun. “Bunsen Burner.” Protons Talk, protonstalk.com/chemistry/bunsen-burner/. Accessed 16 Mar. 2023.
JoVE Science Education Database. “Introduction to the Bunsen Burner.” General Laboratory Techniques, JoVE, www.jove.com/v/5035/introduction-to-the-bunsen-burner. Accessed 16 Mar. 2023.
Markel, Howard, and Ira Flatow. “Science Diction: The Origin of ‘Bunsen Burner.’” National Public Radio, 21 Oct. 2011, www.npr.org/2011/10/21/141591193/science-diction-the-origin-of-bunsen-burner. Accessed 16 Mar. 2023.
McMahon, Mary. “What Is a Bunsen Burner?” All the Science, 3 Mar. 2023, www.allthescience.org/what-is-a-bunsen-burner.htm. Accessed 16 Mar. 2023.
Psiberg Team. “Bunsen Burner: Working, Parts, Types and Uses.” Psiberg, 19 July 2022, psiberg.com/bunsen-burner/. Accessed 16 Mar. 2023.
“Robert Bunsen and Gustav Kirchhoff.” Science History Institute, 20 May 2021, www.sciencehistory.org/historical-profile/robert-bunsen-and-gustav-kirchhoff. Accessed 16 Mar. 2023.